full new version with load and save:

see comments below:

Chrisir ;-)

// Escape is de-activated. 
// using selectInput and selectOutput here. 
// using also setting path dataPath() and file ending "json".
// fileNameForScreen shows the current file name throughout.
// Uses a JSONArray within a JSONObject.

JSONObject json;   // WITHIN this object is an array named animals, see json.setJSONArray("animals", values);

// fileNameForScreen shows the current file name throughout
String fileNameForScreen = "Not a file";

void setup() {
  size(660, 660);
  background(110);

  json = new JSONObject();

  // TWO possible test arrays 
  String[] species = { "Capra hircus", "Panthera pardus", "Equus zebra" };
  String[] names   = { "Goat", "Leopard", "Zebra" };
  // String[] species = { "Cw", "Pp", "Ez" };
  // String[] names   = { "G", "Leo", "Z" };
  //

  // build values (JSONArray) 
  JSONArray values = new JSONArray();

  for (int i = 0; i < species.length; i++) {

    JSONObject animal = new JSONObject();

    animal.setInt("id", i);
    animal.setString("species", species[i]);
    animal.setString("name", names[i]);

    values.setJSONObject(i, animal);
  }//for 

  // add values (JSONArray) to json 
  // comment this out to generate an error 
  json.setJSONArray("animals", values);

  // generate another error for testing outputJSONArray:
  //json = null;
}

void draw() {
  background(110);

  // show Menu
  noFill();
  stroke(0); 
  rect(width-49, 27, 
    45, 80-27);
  fill(0); 
  text("Load\n\n" + "Save", 
    width-44, 44);

  // show file name 
  fill(255); // white 
  text(fileNameForScreen, 
    min(width-44, width - textWidth(fileNameForScreen) - 11), 15);

  // show array 
  outputJSONArray(json, "animals");
}

// --------------------------------------------------------------------------

void keyPressed() {
  // De-activate Escape key 
  if (key==ESC) {
    key=0; // kill Escape
  }
}

void mousePressed() {
  // println (mouseY);
  // right screen border?
  if (mouseX>width-50) {
    checkMouseOnMenu();
  }
}

void checkMouseOnMenu() {

  // using selectInput and selectOutput here. 
  // also setting path and file ending json. 

  if (mouseY>20&&mouseY<47) { 
    //Load
    String fileString = dataPath("") + "\\" +"*.json" ;
    println(fileString);
    File toLoad = new File( fileString ) ;
    selectInput("Load a file:", "fileSelectedForLoad", toLoad);
  } else if (mouseY>48&&mouseY<77) {
    //Save
    String fileString = dataPath("") + "\\*.json" ;
    println(fileString);
    File toSave = new File( fileString ) ;
    selectOutput("Save to a file:", "fileSelectedForSave", toSave);
  } else {
    // ignore
  }
}

// ---------------------------------------------------------------------------------

void fileSelectedForLoad(File selection) {
  File loading;
  loading = selection;
  if (selection == null) {
    println("Window was closed or the user hit cancel.");
  } else { 
    println("User loaded " + selection.getAbsolutePath());
    if (loading  != null) { 
      json =  loadJSONObject(loading.getAbsolutePath());
      fileNameForScreen=loading.getName();//https://docs.oracle.com/javase/7/docs/api/java/io/File.html
    }
  }//else 
  //
}

void fileSelectedForSave(File selection) {
  File saving;
  saving = selection;
  if (selection == null) {
    println("Window was closed or the user hit cancel.");
  } else {
    String saveString = saving.getAbsolutePath();
    saveString=saveString.trim();
    // ending json ok? 
    if (saveString.indexOf(".json") < 0) {
      saveString+=".json"; // very rough approach...
      saving = new File(saveString);
    }
    println("User saved to " + selection.getAbsolutePath());
    if (saving != null) { 
      saveJSONObject(json, saving.getAbsolutePath());
      fileNameForScreen=saving.getName();//https://docs.oracle.com/javase/7/docs/api/java/io/File.html
    }
  }//else 
  //
}

// ---------------------------------------------------------------------------------

void outputJSONArray(JSONObject json, String nameOfJSONArray) {

  // output of an JSONArray named "nameOfJSONArray" in an an JSONObject json.
  // The function is not generic since column names "species" etc. must be correct as below. 

  // error check I. 
  if (json==null) { 
    fill(255, 33, 0); // red 
    text( "No json object", 30, 30+2);
    return;
  }//if 

  JSONArray valuesLoaded =  json.getJSONArray(nameOfJSONArray);

  // error check II. 
  if (valuesLoaded==null) { 
    String error = "No json array named "
      + nameOfJSONArray
      + " in json object.";
    fill(255, 33, 0); // red       
    text(error, 30, 30+2);
    return;
  }//if

  fill(40, 255, 17); // black 

  for (int i = 0; i < valuesLoaded.size(); i++) {

    JSONObject animal = valuesLoaded.getJSONObject(i); 

    int id = animal.getInt("id");
    String species = animal.getString("species");
    String name = animal.getString("name");

    // println(id + ", " + species + ", " + name);
    text(id + ", " + species + ", " + name, 40, 50+35*i); // small table
  }//for 
  //
}//func 
// 

hello! im trying to write a kind of user interface to manage JSON files. What i want is user can store data in JSON files. when mousePressed save a new JSON FILE. here`s my code with a null pointer exception:

 JSONObject json;
File saving;
File loading;

void setup() {
  json = new JSONObject();

}

void draw(){

}

void mousePressed() {
  selectInput("Select a file to process:", "fileSelected");
  saveJSONObject(json, saving.getAbsolutePath());
}




void fileSelected(File selection) {
  saving = selection;
  if (selection == null) {
    println("Window was closed or the user hit cancel.");
  } else { 
    println("User selected " + selection.getAbsolutePath());
  }
}

This is something I had up on this forum since last summer, but it was in a question thread so I thought I should share this here in the proper category as well.

Current version: v1.2

This LaTeX listings template will color your Processing code as you see them in the Processing editor. You can just post your code like you normally would using the listings package, and you will automatically get your code in the proper colors. Except one minor inconvenience, that I will explain here.

For a function name that is the same as an already defined keyword (Such as "boolean" and "boolean()"), you have to use [escapechar = "char"] and \color{"color"}{"text"} to color them properly. Example:

\begin{lstlisting}[escapechar = ?]
boolean;
?\color{function}{boolean}?(1);
\end{lstlisting}

Copy and paste the below template if you want to use it. Alternatively, you can copy only the necessary parts. If in that case, note that \usepackage{listings} and \usepackage{color} is a must for this to work.

Also note, I have licensed this work with CreativeCommons license CC-BY-SA, so please remember to give some credit to me ;)

If you find any typos or any other errors, please tell me and I'll try to fix them as much as possible.

Download version:
http://www.mediafire.com/file/cw861uy156xftkv/article_listing_Processing_v1.2.tex
GitHub Gist:
https://gist.github.com/ebigunso/af355220e932f72d03289c576622aa29

Full template below:

\documentclass{article}

\usepackage{graphicx}
\usepackage{url}
\usepackage{verbatim}
\usepackage{listings}
\usepackage{color}

% Processing language definition template for LaTeX listings package v1.2
%
% Credits to ebigunso for creating this LaTeX listings language definition template for Processing
% This template is licensed with CreativeCommons license CC-BY-SA 4.0
% license info:
% https://creativecommons.org/licenses/by-sa/4.0/legalcode

%Define Colors
\definecolor{black}{RGB}{0,0,0}
\definecolor{gray}{RGB}{102,102,102}        %#666666
\definecolor{function}{RGB}{0,102,153}      %#006699 lightblue
\definecolor{lightgreen}{RGB}{102,153,0}    %#669900
\definecolor{bluegreen}{RGB}{51,153,126}    %#33997e
\definecolor{magenta}{RGB}{217,74,122}  %#d94a7a
\definecolor{orange}{RGB}{226,102,26}       %#e2661a
\definecolor{purple}{RGB}{125,71,147}       %#7d4793
\definecolor{green}{RGB}{113,138,98}        %#718a62

\lstdefinelanguage{Processing}{
  %keyword1&2&6
  morekeywords = [3]{abstract, break, class, continue, default, enum, extends, false, final, finally, implements, import, instanceof, interface, native, new, null, package, private, protected, public, static, strictfp, throws, transient, true, void, volatile, length, assert, case, return, super, this, throw},
  %keyword3
  morekeywords = [4]{catch, do, for, if, else, switch, synchronized, while, try},
  %keyword4
  morekeywords = [5]{width, height, pixelHight, displayHeight, displayWidth, focused, frameCount, frameRate, key, keyCode, keyPressed, mouseButton, mousePressed, mouseX, mouseY, pixels, pixelWidth, pmouseX, pmouseY},
  %keyword5
  morekeywords = [6]{Array, ArrayList, Boolean, Byte, BufferedReader, Character, Class, Double, Float, Integer, HashMap, PrintWriter, String, StringBuffer, StringBuilder, Thread, boolean, byte, char, color, double, float, int, long, short, FloatDict, FloatList, IntDict, IntList, JSONArray, JSONObject, PFont, PGraphics, PImage, PShader, PShape, PVector, StringDict, StringList, Table, TableRow, XML},
  %literal2
  morekeywords = [7]{ADD, ALIGN_CENTER, ALIGN_LEFT, ALIGN_RIGHT, ALPHA, ALPHA_MASK, ALT, AMBIENT, ARC, ARROW, ARGB, BACKSPACE, BASELINE, BEVEL, BLEND, BLUE_MASK, BLUR, BOTTOM, BOX, BURN, CENTER, CHATTER, CHORD, CLAMP, CLICK, CLOSE, CMYK, CODED, COMPLAINT, COMPOSITE, COMPONENT, CONCAVE_POLYGON, CONTROL, CONVEX_POLYGON, CORNER, CORNERS, CROSS, CUSTOM, DARKEST, DEGREES, DEG_TO_RAD, DELETE, DIAMETER, DIFFERENCE, DIFFUSE, DILATE, DIRECTIONAL, DISABLE_ACCURATE_2D, DISABLE_DEPTH_MASK, DISABLE_DEPTH_SORT, DISABLE_DEPTH_TEST, DISABLE_NATIVE_FONTS, DISABLE_OPENGL_ERRORS, DISABLE_PURE_STROKE, DISABLE_TEXTURE_MIPMAPS, DISABLE_TRANSFORM_CACHE, DISABLE_STROKE_PERSPECTIVE, DISABLED, DODGE, DOWN, DRAG, DXF, ELLIPSE, ENABLE_ACCURATE_2D, ENABLE_DEPTH_MASK, ENABLE_DEPTH_SORT, ENABLE_DEPTH_TEST, ENABLE_NATIVE_FONTS, ENABLE_OPENGL_ERRORS, ENABLE_PURE_STROKE, ENABLE_TEXTURE_MIPMAPS, ENABLE_TRANSFORM_CACHE, ENABLE_STROKE_PERSPECTIVE, ENTER, EPSILON, ERODE, ESC, EXCLUSION, EXIT, FX2D, GIF, GRAY, GREEN_MASK, GROUP, HALF, HALF_PI, HAND, HARD_LIGHT, HINT_COUNT, HSB, IMAGE, INVERT, JAVA2D, JPEG, LEFT, LIGHTEST, LINE, LINES, LINUX, MACOSX, MAX_FLOAT, MAX_INT, MIN_FOAT, MIN_INT, MITER, MODEL, MOVE, MULTIPLY, NORMAL, NORMALIZED, NO_DEPTH_TEST, NTSC, ONE, OPAQUE, OPEN, ORTHOGRAPHIC, OVERLAY, PAL, PDF, P2D, P3D, PERSPECTIVE, PI, PIE, PIXEL_CENTER, POINT, POINTS, POSTERIZE, PRESS, PROBLEM, PROJECT, QUAD, QUAD_STRIP, QUADS, QUARTER_PI, RAD_TO_DEG, RADIUS, RADIANS, RECT, RED_MASK, RELEASE, REPEAT, REPLACE, RETURN, RGB, RIGHT, ROUND, SCREEN, SECAM, SHAPE, SHIFT, SPAN, SPECULAR, SPHERE, SOFT_LIGHT, SQUARE, SUBTRACT, SVG, SVIDEO, TAB, TARGA, TAU, TEXT, TFF, THIRD_PI, THRESHOLD, TIFF, TOP, TRIANGLE, TRIANGLE_FAN, TRIANGLES, TRIANGLE_STRIP, TUNER, TWO, TWO_PI, UP, WAIT, WHITESPACE},
  %function1
  morekeywords = [8]{start, stop, breakShape, createPath, str, loadMatrix, parseBoolean, parseByte, parseChar, parseFloat, parseInt, saveFile, savePath, sketchFile, sketchPath, abs, acos, alpha, ambient, ambientLight, append, applyMatrix, arc, arrayCopy, asin, atan, atan2, background, beginCamera, beginContour, beginRaw, beginRecord, beginShape, bezier, bezierDetail, bezierPoint, bezierTangent, bezierVertex, binary, blend, blendColor, blendMode, blue, box, brightness, camera, ceil, clear, clip, color, colorMode, concat, constrain, copy, cos, createFont, createGraphics, createImage, createInput, createOutput, createReader, createShape, createWriter, cursor, curve, curveDetail, curvePoint, curveTangent, curveTightness, curveVertex, day, degrees, delay, directionalLight, displayDensity, dist, ellipse, ellipseMode, emissive, endCamera, endContour, endRaw, endRecord, endShape, exit, exp, expand, fill, filter, floor, frustum, fullScreen, get, green, hex, hint, hour, hue, image, imageMode, join, launch, lerp, lerpColor, lightFalloff, lights, lightSpecular, line, loadBytes, loadFont, loadImage, loadJSONArray, loadJSONObject, loadPixels, loadShader, loadShape, loadStrings, loadTable, loadXML, log, loop, mag, map, match, matchAll, max, millis, min, minute, modelX, modelY, modelZ, month, nf, nfc, nfp, nfs, noClip, noCursor, noFill, noise, noiseDetail, noiseSeed, noLights, noLoop, norm, normal, noSmooth, noStroke, noTint, ortho, parseJSONArray, parseJSONObject, parseXML, perspective, list, pixelDnsity, point, pointLight, popMatrix, popStyle, pow, print, printArray, printCamera, println, printMatrix, printProjection, pushMatrix, pushStyle, quad, quadraticVertex, radians, random, randomGaussian, randomSeed, rect, rectMode, red, redraw, requestImage, resetMatrix, resetShader, reverse, rotate, rotateX, rotateY, rotateZ, round, saturation, save, saveBytes, saveFrame, saveJSONArray, saveJSONObject, saveStream, saveStrings, saveTable, saveXML, scale, screenX, screenY, screenZ, second, selectFolder, selectInput, selectOutput, set, shader, shape, shapeMode, shearX, shearY, shininess, shorten, sin, size, smooth, sort, specular, sphere, sphereDetail, splice, split, splitTokens, spotLight, sq, sqrt, stroke, strokeCap, strokeJoin, strokeWeight, subset, tan, text, textAlign, textAscent, textDescent, textFont, textLeading, textMode, textSize, texture, textureMode, textureWrap, textWidth, thread, tint, translate, triangle, trim, unbinary, unhex, updatePixels, vertex, year},
  %function2
  morekeywords = [9]{cache, readLine, close, flush, print, println, charAt, equals, indexOf, substring, toLowerCase, toUpperCase, getDouble, getLong, getColumnTitles, getColumnTypes, getColumnType, setDouble, setLong, add, clear, div, get, hasKey, keyArray, keys, mult, remove, set, size, sortKeys, sortKeysReverse, sortValues, sortValuesReverse, sub, valueArray, values, append, array, hasValue, max, min, mult, remove, reverse, shuffle, sort, sortReverse, increment, getBoolean, getFloat, getInt, getIntArray, getJSONArray, getJSONObject, getString, getStringArray, isNull, setBoolean, setFloat, setInt, setJSONArray, setJSONObject, setString, beginDraw, endDraw, blend, copy, filter, loadPixels, mask, resize, save, updatePixels, addChild, beginContour, beginShape, disableStyle, enableStyle, endContour, endShape, getChild, getChildCount, getVertex, getVertexCount, isVisible, resetMatrix, rotate, rotateX, rotateY, rotateZ, scae, setFill, setStroke, setVertex, setVisible, translate, angleBetween, cross, dist, dot, fromAngle, heading, lerp, limit, mag, magSq, normalize, randm2D, random3D, setMag, lower, upper, addColumn, addRow, clearRows, findRow, findRows, getColumnCount, getRow, getRowcount, getStringColumn, matchRow, matchRows, removeColumn, removeRow, removeTokens, rows, trim, getColumnTitle, format, getAttributeCount, getChildren, getContent, getNam, getParent, hasAttribute, hasChildren, listAttributes, listChildren, removeChild, setContent, setName, toString},
  %function4
  morekeywords = [10]{draw, keyReleased, keyTyped, mouseClicked, mouseDragged, mouseMoved, mouseReleased, mouseWheel, settings, setup},
  keywordstyle = [3]\color{bluegreen},
  keywordstyle = [4]\color{lightgreen},
  keywordstyle = [5]\color{magenta},
  keywordstyle = [6]\color{orange},
  keywordstyle = [7]\color{green},
  keywordstyle = [8]\color{function},
  keywordstyle = [9]\color{function},
  keywordstyle = [10]\color{function},
  sensitive = true,
  morecomment = [l][\color{gray}]{//},
  morecomment = [s][\color{gray}]{/*}{*/},
  morecomment = [s][\color{gray}]{/**}{*/},
  morestring = [b][\color{purple}]",
  morestring = [b][\color{purple}]'
}
\renewcommand{\ttdefault}{pcr}
\lstset{
  language={Processing},
  basicstyle={\small\ttfamily},
  identifierstyle={\small},
  commentstyle={\small\itshape},
  keywordstyle={\small},
  ndkeywordstyle={\small},
  stringstyle={\small\ttfamily},
  frame={tb},
  breaklines=true,
  columns=[l]{fullflexible},
  numbers=left,
  xrightmargin=0em,
  xleftmargin=3em,
  numberstyle={\scriptsize},
  stepnumber=1,
  numbersep=1em,
  lineskip=-0.5ex,
}

% Use escapechar and \color{<color>}{<text>} to color function names properly, that is already defined as a different color keyword.
%
% \begin{lstlisting}[escapechar = ?]
% boolean;
% ?\color{function}{boolean}?(1);
% \end{lstlisting}

\title{}
\author{}
\date{}

\begin{document}
\maketitle
\section{}

\begin{thebibliography}{9}
\end{thebibliography}
\end{document}

  fill(255, 2, 2);
  text("My little Graph program\n\nUse buttons on the right and below;\n"    //testo e posizione testo
    +"use Backspace to delete last data point of each list.\n\n"
    +"Use 1 and 2 to set the active table which is marked by the horizontal line on top.\n"
    +"New, Load and Save are referring to the active table (and also Backspace).\n\n"
    +"You can click now above each column to activate it.\n"
    +"You can press m to hide/show data text and x to show / hide quick help."
    +"\n\nHit any key to return to main program.", 
    113, 122, width-200, 422);
}

// --------------------------------------------------
// functions to show buttons funzione per mostrare i bottoni

void showButtons() {
  //
  strokeWeight(2);   
  stroke(0);
  textSize(15);

  fill(0);
  if ( overSave() ) {
    fill(#FF0303);
  }

  rect(width-50, height-740, 40, 20, 5);// modificato posizione bottone "salve"
  fill(255); 
  text("Save", 
    width-50+2, height-740+9+6);

  // ---

  fill(0);
  if ( overLoad() ) {
    fill(#49C3FA);
  }

  rect(width-50, height-710, 40, 20, 5);// modificato posizione" load"
  fill(255); 
  text("Load", 
    width-50+2, height-710+9+6);

  // ---

  fill(0);
  if ( overNew() ) {
    fill(#1FFF03);
  }

  rect(width-50, height-680, 40, 20, 5);// modificato posizione "new"
  fill(255); 
  text("New", 
    width-50+4, height-680+9+6);

  // ---

  fill(0);
  if ( overHelp() ) {
    fill(#1AAF03);
  }
  rect(width-50, height-650, 40, 20, 5);// modificato posizione "help"
  fill(255); 
  text("Help", 
    width-50+4, height-650+9+6);
}

//----------------------------------------------------------------------------
// functions to register if mouse is over buttons funzione da registrare se il mouse è sui pulsanti

boolean overSave() {            // modificato
  return mouseX > width-50 && 
    mouseY > height-740  && 
    mouseY < height-740+25 ;
}

boolean overLoad() {                 //modificato
  return mouseX > width-50 && 
    mouseY > height-710  && 
    mouseY < height-710+25 ;
}

boolean overNew() {                         //modificato
  return mouseX > width -50 && 
    mouseY > height-680  && 
    mouseY < height-680+25 ;
}

boolean overHelp() {                         //modificato
  return mouseX > width -50 && 
    mouseY > height-650  && 
    mouseY < height-650+25 ;
}

// ---------------------------------------------------------------------------
// Inputs 

void keyPressed() {

  if (state==help) {
    goBackToMainState();
    return;
  }

  if (state!=normal)
    return;

  //  
  if (  keyCode == BACKSPACE ) {
    //
    backspaceOnActiveList();
    //
  } 
  // ----
  else if ( keyCode == DELETE ) {
    //
    // ignore 
    //
  } else if  ( keyCode == ESC ) {
    //
    // If yellow help box is ON  
    if (showHelpText1) {
      showHelpText1 = false; // yellow help box off
    } else {
      // else toggle
      showText = !showText; // data text / tables
    }//else 
    // kill Esc so we stay in the program 
    key=0;
    //
  } 

  // ------

  else {
    if ( key != CODED ) {
      //
      switch(key) {

      case '0':
        activeArrayListHasNumber = 0; 
        break;

      case '1':
        activeArrayListHasNumber = 1; 
        break;

      case '2':
        activeArrayListHasNumber = 2; 
        break;

      case '3':
        activeArrayListHasNumber = 3; 
        break;

      case 'x':
        showHelpText1 = !showHelpText1; // yellow help box 
        break;

      case 'm':
        showText = !showText; // data text / tables 
        break;
        //
      }//switch
      //
    }//if
  }//else
}// func 

void mousePressed() {

  if (state==help) {
    goBackToMainState();
    return;
  }

  if (state!=normal)
    return;

  // for the buttons 
  if ( overSave() ) {
    initSave();
  }
  //---
  else if ( overLoad() ) {
    initLoad();
  } else if ( overHelp() ) {
    state=help;
  }
  //---
  else if ( overNew() ) {
    //
    if ( activeArrayListHasNumber==0 ) {
      points1.clear();            //cancellare punti con new
    } else if ( activeArrayListHasNumber==1 ) {
      points2.clear();            //cancellare punti con new
    } else if ( activeArrayListHasNumber==2 ) {
      points3.clear();            //cancellare punti con new
    } else if ( activeArrayListHasNumber==3 ) {
      points4.clear();            //cancellare punti con new
    }// else if

    // set name 
    fileNames[activeArrayListHasNumber] = "not a File"; 
    //
  }
  //---

  boolean done = false; 

  if (mouseY>390 && mouseY<425){
    for (int i=0; i < arrayOfXValuesFrom.length; i++) {
      if (mouseX>arrayOfXValuesFrom[i] && 
        mouseX<arrayOfXValuesTo[i]) { 
        //
        activeArrayListHasNumber=i;
        done = true; 
        break;
      }//if
    }//for
  }//if

  if (!done) {
    // points.add(new PVector(points.size(), mouseY/10));
    if ( activeArrayListHasNumber == 0 ) {
       points1.add(new PVector(points1.size(), MasA));
     // points1.add(new PVector(points1.size(), mouseY));
    } else if ( activeArrayListHasNumber == 1 ) {
      points2.add(new PVector(points2.size(), MasA));
      //points2.add(new PVector(points2.size(), mouseY));
    } else if ( activeArrayListHasNumber == 2 ) {
      points3.add(new PVector(points3.size(), MasA));
      //points3.add(new PVector(points3.size(), mouseY));
    } else if ( activeArrayListHasNumber == 3 ) {
      //points2.add(new PVector(points2.size(), MasA.getValue()));
      //points4.add(new PVector(points4.size(), mouseY));
      points4.add(new PVector(points4.size(), MasA));
    }
  }
}//func

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath=""; 
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-"
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2); 
  // prepare fileDescription which occurs in the dialogue
  // prepara la descrizione del file che avviene nel dialogo
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//"
    + dateTimeStamp
    + fileExtension); 
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription); 
  // set state to wait
  state=save;
}

void initLoad() {
  // init load process 
  // reset
  loadPath=""; 
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension ); 
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription); 
  // set state to wait
  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");


    // println ("La finestra è stata chiusa o l'utente ha premuto annulla.");
    // torna indietro

    state=normal; // go back
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");

    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt(); 
    // go back 
    state=normal;
  }
}
void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt(); 
    // go back 
    state=normal;
  }
}

void saveIt() {
  // save

  // make array (to save it)
  String[] strs; 
  strs = new String[0]; 

  if (activeArrayListHasNumber==0) {
    strs = new String[points1.size()]; 
    int i=0; 
    for (PVector pv : points1) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }// 
  else if (activeArrayListHasNumber==1) {
    strs = new String[points2.size()]; 
    int i=0; 
    for (PVector pv : points2) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }//else
  else if (activeArrayListHasNumber==2) {
    strs = new String[points3.size()]; 
    int i=0; 
    for (PVector pv : points3) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }//else
  else if (activeArrayListHasNumber==3) {
    strs = new String[points4.size()]; 
    int i=0; 
    for (PVector pv : points4) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }//else

  // check if file extension (fileExtension, e.g. .txt) is there 
  int len = savePath.length(); 
  if (len<4 || !savePath.substring( len-4 ).equals(fileExtension)) {
    // file Extension is not present, we have to add it
    savePath += fileExtension; // add the file Extension
  } 

  // save 
  println("Saved: " + savePath); 
  saveStrings( savePath, strs );

  // get file name for list 
  fileNames[activeArrayListHasNumber] =  nameFromPath(savePath);
} //func

void loadIt() {
  // load
  if (activeArrayListHasNumber==0)
  {
    points1.clear();
  } else if (activeArrayListHasNumber==1)
  {
    points2.clear();
  } else if (activeArrayListHasNumber==2)
  {
    points3.clear();
  } else if (activeArrayListHasNumber==3)
  {
    points4.clear();
  }

  fileNames[activeArrayListHasNumber] =  nameFromPath(loadPath); 

  String[] strs = loadStrings( loadPath ); 
  for (String s : strs) {
    String[] thisLine=split(s, ","); 

    if (activeArrayListHasNumber==0) 
    {
      points1.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    } else if (activeArrayListHasNumber==1)
    {
      points2.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    } else if (activeArrayListHasNumber==2)
    {
      points3.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    } else if (activeArrayListHasNumber==3)
    {
      points4.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    }//else
    //
  }//for
}//func 

// -------------------------------------------------

void showData1() {
  //
  // show data 1

  PVector prev = new PVector(-1, -1); 
  int y=50; 

  if (activeArrayListHasNumber==0) {
    stroke(255, 2, 2); // RED
    line (900, 405, 990, 405);  //linea sopra tabella
    line (870, 260, 1330, 260); 
    line (870, 280, 1330, 280);// linee text file
    ellipse (865, 270, 6, 6);
  }

  for (PVector pv : points1) {

    if (showText) {
      fill(255, 2, 2); // RED 
      // show data
      text(pv.x, 970-50, y+410); 
      text(pv.y, 970, y+410);
    }

    fill(0, 2, 2); 
    stroke(255, 2, 2); // RED 
    float yvalue = map( pv.y, 0,1, 700, 180); //mappatura linea grafica RED
    if (prev.x!=-1) {
      line(80 + pv.x*55, yvalue, 
        prev.x, prev.y);// linea grafico red
    }
    stroke(150); 
     ellipse (80 + pv.x*55, yvalue, 4, 4);
    prev = new PVector(80 + pv.x*55, yvalue); 


    y+=20; //next line
  }//for

  if (showText) {
    // middle line 
    stroke(255, 2, 2); // RED 
    line(1275-330,440, 1275-330,720);

  }
  //
}

void showData2() {
  //
  // show data 2 

  if (activeArrayListHasNumber==1) {
    // activeArrayListHasNumber is FALSE, right side is active
    stroke(2, 255, 2); // GREEN
    line (1010, 405, 1100, 405);
    line (870, 290, 1330, 290);
    line (870, 310, 1330, 310);// linee text file
    ellipse (865, 300, 6, 6);

  }

// https : // forum.processing.org/two/discussion/26719/save-and-load-array-list#latest

import processing.serial.*; 
import controlP5.*;   
import grafica.*;

Serial myPort;      // The serial port: 
ControlP5 controlP5;   // controlP5 object
Knob myKnob1, myKnob2, myKnob3, myKnob4;  // knobs 

// buttons above columns
int[] arrayOfXValuesFrom = { 13, 220, 390, 570 };  
int[] arrayOfXValuesTo = { 193, 340, 550, 710 };

// text for file names for each column 
String[] fileNames = { "not a file", 
  "not a file", 
  "not a file", 
  "not a file" };  

// 4 columns 
ArrayList<PVector> points1 = new ArrayList(); // 1st 
ArrayList<PVector> points2 = new ArrayList(); // 2nd
ArrayList<PVector> points3 = new ArrayList(); // 3rd 
ArrayList<PVector> points4 = new ArrayList(); // 4th

// active column 
int activeArrayListHasNumber = 0;  

// some flags for texts 
boolean showHelpText1 = false; 
boolean showText = true; 

String inString;  // Input string from serial port: 
int lf = 10;      // ASCII linefeed 
float deg, val;

final String pathFolder="";//CARTELLA DI PERCORSO
final String fileExtension = ".txt";//estensione file

// unique numbers for constants: 
final int normal = 0;
final int save   = 1;
final int load   = 2;
final int help   = 3;
/// current state (must be one of them) 
/// stato attuale (deve essere uno di loro)
int state=normal;

// Paths 
String savePath=""; 
String loadPath=""; 

// --------------------------------------------------------------------------

void setup() {
  size(1350, 750);

  // not necessary
  for (int i = 0; i < 3; i++) { 
    points1.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for
  for (int i = 0; i < 13; i++) { 
    points2.add(new PVector(i, 30 + 10*noise(i*0.1)));
  }//for
  for (int i = 0; i < 5; i++) { 
    points3.add(new PVector(i, 40 + 10*noise(i*0.1)));
  }//for
  for (int i = 0; i < 7; i++) { 
    points4.add(new PVector(i, 50 + 10*noise(i*0.1)));
  }//for

  //ControlP5
  PFont  f= createFont ("Georgia", 25);
  {
    controlP5 = new ControlP5(this);   //ControlP5

    myKnob1 = controlP5.addKnob(" Massa ARIA")
      //.setRange(0,1024)
      .setRange(0, 5)
      .setValue(0)
      .setPosition(width-370, height-185)//posizione 605
      .setTickMarkLength(10)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //  . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      . setDecimalPrecision(2) //numero dopo la virgola
      ;
    myKnob1 .getCaptionLabel()
      . setFont(f);
    myKnob1.getValueLabel()
      .setFont(f)
      ;
    ;

    myKnob2 = controlP5.addKnob("P. Cil")
      .setRange(0, 500)
      .setValue(0)
      .setPosition(width-370, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      // . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      .  setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10) 
      ;
    myKnob2 .getCaptionLabel()
      . setFont(f);
    myKnob2.getValueLabel()
      .setFont(f)
      ;

    myKnob3 = controlP5.addKnob("P. Atm ")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob3 .getCaptionLabel()
      . setFont(f);
    myKnob3.getValueLabel()
      .setFont(f)
      ;

    myKnob4 = controlP5.addKnob("temp")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-185)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob4 .getCaptionLabel()
      . setFont(f);
    myKnob4.getValueLabel()
      .setFont(f)
      ;
  }

  //  myPort = new Serial(this, "com3", 9600);  // ?????
  //  myPort.bufferUntil(lf);
}

void draw() {

  switch (state) {

  case normal:
    drawForStateNormal() ;
    break; 

  case save:
    // wait for Save Dialog 
    waitForSaveDialog();
    break; 

  case load:
    // wait for Load Dialog 
    waitForLoadDialog();
    break;

  case help:
    // help
    drawForStateHelp() ;
    break; 

  default:
    //Error 
    println("Fail 192; unknown state: "
      +state);
    exit();
    break; 
    //
  } //switch
  //
}//func

// ------------------------------------------------

void drawForStateNormal() {

  background(245);
  {
    strokeWeight(2);   
    stroke(#FF0B03);
    fill(0);
    rect(width-380, height-490, 360, 90, 20);// retangolo diff. press.
    fill(255);
    textSize(28); 
    text("Diff.Press.", width-270, height-405);     //diff.press
    textSize(40);
    text(( myKnob2.getValue()- myKnob3.getValue()), width-270, height-445);     //diff.press
  }
  {
    fill(0);
    strokeWeight(2);   
    stroke(#FF0B03);

    rect(width-380, height-390, 360, 190, 20);// retangolo press
    rect(width-380, height-195, 360, 190, 20);// rettangolo massa Temp
  }
  textSize(14);
  showData1();
  showData2();
  showData3();
  showData4();

  // title 
  fill(255, 2, 2);
  textAlign(CENTER);
  text("My little\nGraph program", 
    width-223, 19, 130, 422);
  //reset 
  textAlign(LEFT);

  //// help
  if (showHelpText1) {
    float widthOfBox = 210; 
    fill(240, 544, 2); // yellow 
    stroke(0);         // black 
    rect(420, 27, widthOfBox, 322);
    fill(0);           // black 
    text("Use mouse above columns (or 0..3) to set the active table "
      +"which is marked by the horizontal line on top.\n\n"
      +"New, Load and Save are referring to the active table (and Backspace).\n"
      +"m to hide / show text data.\n\nHit x to hide / show this text.", 
      425, 30, widthOfBox-10, 522);
  }

  // ----------------------
  // buttons
  showButtons();

  // gray lines above columns 
  for (int i=0; i < arrayOfXValuesFrom.length; i++) {
    if (activeArrayListHasNumber!=i) {
      stroke(111); //
      strokeWeight(2.8); 
      line (arrayOfXValuesFrom [i], 10, 
        arrayOfXValuesTo[i], 10);
      strokeWeight(0.8); 
      line (arrayOfXValuesFrom [i]+10, 14, 
        arrayOfXValuesTo[i]-10, 14);
      line (arrayOfXValuesFrom [i]+10, 10-4, 
        arrayOfXValuesTo[i]-10, 10-4);
    }//if 
    fill(0);
    text (fileNames[i], 
      arrayOfXValuesFrom [i], height-18);
  }//for 

  // reset
  strokeWeight(1.0); 
  //
} //draw

void drawForStateHelp() {

  // Help

  background(245);
  myKnob1.setVisible(false);
  myKnob2.setVisible(false);
  myKnob3.setVisible(false);
  myKnob4.setVisible(false); 

  fill(255, 2, 2);
  text("My little Graph program\n\nUse buttons on the right and below;\n"    //testo e posizione testo
    +"use Backspace to delete last data point of each list.\n\n" 
    +"Use 1 and 2 to set the active table which is marked by the horizontal line on top.\n"
    +"New, Load and Save are referring to the active table (and also Backspace).\n\n"
    +"You can click now above each column to activate it.\n"
    +"You can press m to hide/show data text and x to show / hide quick help."
    +"\n\nHit any key to return to main program.", 
    113, 122, width-200, 422);
}

// --------------------------------------------------
// functions to show buttons funzione per mostrare i bottoni

void showButtons() {
  //
  strokeWeight(2);   
  stroke(0);
  textSize(15);

  fill(0);
  if ( overSave() ) {
    fill(#FF0303);
  }

  rect(width-50, height-740, 40, 20, 5);// modificato posizione bottone "salve"
  fill(255); 
  text("Save", 
    width-50+2, height-740+9+6);

  // ---

  fill(0);
  if ( overLoad() ) {
    fill(#49C3FA);
  }

  rect(width-50, height-710, 40, 20, 5);// modificato posizione" load"
  fill(255); 
  text("Load", 
    width-50+2, height-710+9+6);

  // ---

  fill(0);
  if ( overNew() ) {
    fill(#1FFF03);
  }

  rect(width-50, height-680, 40, 20, 5);// modificato posizione "new"
  fill(255); 
  text("New", 
    width-50+4, height-680+9+6);

  // ---

  fill(0);
  if ( overHelp() ) {
    fill(#1AAF03);
  }
  rect(width-50, height-650, 40, 20, 5);// modificato posizione "help"
  fill(255); 
  text("Help", 
    width-50+4, height-650+9+6);
}

//----------------------------------------------------------------------------
// functions to register if mouse is over buttons funzione da registrare se il mouse è sui pulsanti

boolean overSave() {            // modificato
  return mouseX > width-50 && 
    mouseY > height-740  && 
    mouseY < height-740+25 ;
}

boolean overLoad() {                 //modificato
  return mouseX > width-50 && 
    mouseY > height-710  && 
    mouseY < height-710+25 ;
}

boolean overNew() {                         //modificato
  return mouseX > width -50 && 
    mouseY > height-680  && 
    mouseY < height-680+25 ;
}

boolean overHelp() {                         //modificato
  return mouseX > width -50 && 
    mouseY > height-650  && 
    mouseY < height-650+25 ;
}

// ---------------------------------------------------------------------------
// Inputs 

void keyPressed() {

  if (state==help) {
    goBackToMainState();
    return;
  }

  if (state!=normal)
    return;

  //  
  if (  keyCode == BACKSPACE ) {
    //
    backspaceOnActiveList();
    //
  } 
  // ----
  else if ( keyCode == DELETE ) {
    //
    // ignore 
    //
  } else if  ( keyCode == ESC ) {
    //
    // If yellow help box is ON  
    if (showHelpText1) {
      showHelpText1 = false; // yellow help box off
    } else {
      // else toggle
      showText = !showText; // data text / tables
    }//else 
    // kill Esc so we stay in the program 
    key=0;
    //
  } 

  // ------

  else {
    if ( key != CODED ) {
      //
      switch(key) {

      case '0':
        activeArrayListHasNumber = 0; 
        break;

      case '1':
        activeArrayListHasNumber = 1; 
        break;

      case '2':
        activeArrayListHasNumber = 2; 
        break;

      case '3':
        activeArrayListHasNumber = 3; 
        break;

      case 'x':
        showHelpText1 = !showHelpText1; // yellow help box 
        break;

      case 'm':
        showText = !showText; // data text / tables 
        break;
        //
      }//switch
      //
    }//if
  }//else
}// func 

void mousePressed() {

  if (state==help) {
    goBackToMainState();
    return;
  }

  if (state!=normal)
    return;

  // for the buttons 
  if ( overSave() ) {
    initSave();
  }
  //---
  else if ( overLoad() ) {
    initLoad();
  } else if ( overHelp() ) {
    state=help;
  }
  //---
  else if ( overNew() ) {
    //
    if ( activeArrayListHasNumber==0 ) {
      points1.clear();            //cancellare punti con new
    } else if ( activeArrayListHasNumber==1 ) {
      points2.clear();            //cancellare punti con new
    } else if ( activeArrayListHasNumber==2 ) {
      points3.clear();            //cancellare punti con new
    } else if ( activeArrayListHasNumber==3 ) {
      points4.clear();            //cancellare punti con new
    }// else if

    // set name 
    fileNames[activeArrayListHasNumber] = "not a File"; 
    //
  }
  //---

  boolean done = false; 

  if (mouseY<25) {
    for (int i=0; i < arrayOfXValuesFrom.length; i++) {
      if (mouseX>arrayOfXValuesFrom[i] && 
        mouseX<arrayOfXValuesTo[i]) { 
        //
        activeArrayListHasNumber=i;
        done = true; 
        break;
      }//if
    }//for
  }//if

  if (!done) {
    // points.add(new PVector(points.size(), mouseY/10));
    if ( activeArrayListHasNumber == 0 ) {
      // points1.add(new PVector(points1.size(), myKnob1.getValue()));
      points1.add(new PVector(points1.size(), mouseY));
    } else if ( activeArrayListHasNumber == 1 ) {
      //points2.add(new PVector(points2.size(), myKnob1.getValue()));
      points2.add(new PVector(points2.size(), mouseY));
    } else if ( activeArrayListHasNumber == 2 ) {
      //points2.add(new PVector(points2.size(), myKnob1.getValue()));
      points3.add(new PVector(points3.size(), mouseY));
    } else if ( activeArrayListHasNumber == 3 ) {
      //points2.add(new PVector(points2.size(), myKnob1.getValue()));
      points4.add(new PVector(points4.size(), mouseY));
    }
  }
}//func

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath=""; 
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-"
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2); 
  // prepare fileDescription which occurs in the dialogue
  // prepara la descrizione del file che avviene nel dialogo
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//"
    + dateTimeStamp
    + fileExtension); 
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription); 
  // set state to wait
  state=save;
}

void initLoad() {
  // init load process 
  // reset
  loadPath=""; 
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension ); 
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription); 
  // set state to wait
  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");


    // println ("La finestra è stata chiusa o l'utente ha premuto annulla.");
    // torna indietro

    state=normal; // go back
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");

    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt(); 
    // go back 
    state=normal;
  }
}

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath=""; 
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-"
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2); 
  // prepare fileDescription which occurs in the dialogue
  // prepara la descrizione del file che avviene nel dialogo
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//"
    + dateTimeStamp
    + fileExtension); 
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription); 
  // set state to wait
  state=save;
}

void initLoad() {
  // init load process 
  // reset
  loadPath=""; 
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension ); 
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription); 
  // set state to wait
  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");


    // println ("La finestra è stata chiusa o l'utente ha premuto annulla.");
    // torna indietro

    state=normal; // go back
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");

    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt(); 
    // go back 
    state=normal;
  }
}

void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt(); 
    // go back 
    state=normal;
  }
}

void saveIt() {
  // save

  // make array (to save it)

  String[] strs; 
  strs = new String[0]; 

  if (activeArrayListHasNumber==0) {
    strs = new String[points1.size()]; 
    int i=0; 
    for (PVector pv : points1) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }// 
  else if (activeArrayListHasNumber==1) {
    strs = new String[points2.size()]; 
    int i=0; 
    for (PVector pv : points2) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }//else
  else if (activeArrayListHasNumber==2) {
    strs = new String[points3.size()]; 
    int i=0; 
    for (PVector pv : points3) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }//else
  else if (activeArrayListHasNumber==3) {
    strs = new String[points4.size()]; 
    int i=0; 
    for (PVector pv : points4) {
      strs[i]=str(pv.x)+","+str(pv.y); 
      i++;
    }//for
  }//else

  // check if file extension (fileExtension, e.g. .txt) is there 
  int len = savePath.length(); 
  if (len<4 || !savePath.substring( len-4 ).equals(fileExtension)) {
    // file Extension is not present, we have to add it
    savePath += fileExtension; // add the file Extension
  } 

  // save 
  println("Saved: " + savePath); 
  saveStrings( savePath, strs );
}//func

void loadIt() {
  // load
  if (activeArrayListHasNumber==0) {
    points1.clear();
  } else if (activeArrayListHasNumber==1)
  {
    points2.clear();
  } else if (activeArrayListHasNumber==2)
  {
    points3.clear();
  } else if (activeArrayListHasNumber==3)
  {
    points4.clear();
  }

  String[] strs = loadStrings( loadPath ); 
  for (String s : strs) {
    String[] thisLine=split(s, ","); 

    if (activeArrayListHasNumber==0) {
      points1.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    } else if (activeArrayListHasNumber==1)
    {
      points2.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    }//else
    else if (activeArrayListHasNumber==2)
    {
      points3.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    }//else
    else if (activeArrayListHasNumber==3)
    {
      points4.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    }//else
    //
  }//for
}

// -------------------------------------------------

void showData1() {
  //
  // show data 1

  PVector prev = new PVector(-1, -1); 
  int y=50; 

  if (activeArrayListHasNumber==0) {
    stroke(255, 2, 2); // RED
    line (10, 10, 198, 10);
  }

  for (PVector pv : points1) {

    if (showText) {
      fill(255, 2, 2); // RED 
      // show data
      text(pv.x, 30, y); 
      text(pv.y, 110, y);
    }

    fill(0, 2, 2); 
    stroke(255, 2, 2); // RED 
    float yvalue = map( pv.y, 0, height, 300, 355); 
    if (prev.x!=-1) {
      line(10 + pv.x*3, yvalue, 
        prev.x, prev.y);
    }
    noStroke(); 
    // ellipse (10 + pv.x*3, yvalue, 4, 4);
    prev = new PVector(10 + pv.x*3, yvalue); 


    y+=20; //next line
  }//for

  if (showText) {
    // middle line 
    stroke(255, 2, 2); // RED 
    line( 100, 30, 100, height);

    // double middle lines!!!   
    stroke(0); // BLACK 
    int x1=200; 
    line( x1-2, 30, x1-2, height); 
    line( x1+2, 30, x1+2, height);
  }
  //
}

void showData2() {
  //
  // show data 2 

  if (activeArrayListHasNumber==1) {
    // activeArrayListHasNumber is FALSE, right side is active
    stroke(2, 255, 2); // GREEN
    line (200, 10, 
      350, 10);
  }

  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points2) {

    if (showText) {
      fill(0, 255, 2); // GREEN 
      // show data
      text(pv.x, 210, y); 
      text(pv.y, 210+80, y);
    }

    fill(0, 2, 2); 
    stroke(0, 255, 2); // GREEN 
    float yvalue = map( pv.y, 0, height, 300, 355); 
    if (prev.x!=-1) {
      line(10 + pv.x*3, yvalue, 
        prev.x, prev.y);
    }
    noStroke(); 
    //   ellipse (10 + pv.x*3, yvalue, 4, 4);
    prev = new PVector(10 + pv.x*3, yvalue); 

    y+=20; //next line
  }//for

  if (showText) {
    // middle line 
    stroke(0, 255, 2); // GREEN 
    line( 288, 30, 288, height);

    // double middle lines!!!   
    stroke(0); // BLACK 
    int x1=210+80+80; 
    line( x1-2, 30, x1-2, height); 
    line( x1+2, 30, x1+2, height);
  }
  //
}

void showData3() {
  //
  // show data 3

  color col3 = color(0, 2, 255); // BLUE 

  if (activeArrayListHasNumber==2) {
    // activeArrayListHasNumber is FALSE, right side is active
    stroke(col3); // 
    line (400, 10, 
      550, 10);
  }

  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points3) {

    fill(col3); // Blue 

    if (showText) {
      // show data
      text(pv.x, 210+180, y); 
      text(pv.y, 210+180+80, y);
    }

    fill(0, 2, 2); 
    stroke(col3); // blue 
    float yvalue = map( pv.y, 0, height, 300, 355); 
    if (prev.x!=-1) {
      line(10 + pv.x*3, yvalue, 
        prev.x, prev.y);
    }
    noStroke(); 
    //   ellipse (10 + pv.x*3, yvalue, 4, 4);
    prev = new PVector(10 + pv.x*3, yvalue); 

    y+=20; //next line
  }//for

  if (showText) {
    // middle line 
    stroke(col3); // blue 
    line( 467, 30, 467, height);

    // double middle lines!!!   
    stroke(0); // BLACK 
    int x1=210+180+80+80; 
    line( x1-2, 30, x1-2, height); 
    line( x1+2, 30, x1+2, height);
  }
  //
}

void showData4() {
  //
  // show data 4 

  color col4 = color(155, 255, 112); 

  if (activeArrayListHasNumber==3) {
    // activeArrayListHasNumber is FALSE, right side is active
    stroke(col4); // 
    line (570, 10, 
      710, 10);
  }

  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points4) {

    fill(col4); //  

    if (showText) {
      // show data
      text(pv.x, 210+180+180, y); 
      text(pv.y, 210+180+180+80, y);
    }

    fill(0, 2, 2); 
    stroke(col4); //  
    float yvalue = map( pv.y, 0, height, 300, 355); 
    if (prev.x!=-1) {
      line(10 + pv.x*3, yvalue, 
        prev.x, prev.y);
    }
    noStroke(); 
    //   ellipse (10 + pv.x*3, yvalue, 4, 4);
    prev = new PVector(10 + pv.x*3, yvalue); 

    y+=20; //next line
  }//for

  if (showText) {
    // middle line 
    stroke(col4); //  
    line( 210+180+180+80-4, 30, 210+180+180+80-4, height);
  }
  //
}

// ---------------------------------------------------------------

void serialEvent(Serial p) { 
  inString = p.readString(); 
  char primo=inString.charAt(0); // primo carattere
  String cifra=inString.substring(1); // da secondo carattere in poi
  float val=parseFloat(cifra); // valore da 0-255 o 0-1023, non sò cosa spedisce arduino


  print("val="); 
  println(val); 

  //   inString = trim(inString);

  //    // converte in int e mappa all'altezza dello schermo: 


  switch(primo) { 
    case ('A') : 
    myKnob1.setValue(val); 
    break; 
    case ('B') : 
    myKnob2.setValue(val); 
    break; 
    case ('C') : 
    myKnob3.setValue(val); 
    break; 
    case ('D') : 
    myKnob3.setValue(val); 
    break;
  }
}

void goBackToMainState() {

  // from help screen back to main screen

  // buttons ON 
  myKnob1.setVisible(true); 
  myKnob2.setVisible(true); 
  myKnob3.setVisible(true); 
  myKnob4.setVisible(true); 

  //go back to main screen 
  state=normal;

  // kill Esc so we stay in the program 
  key=0;
}

void  backspaceOnActiveList() {

  // for the key BACKSPACE 

  switch (activeArrayListHasNumber) {

  case 0:
    if (points1.size()>0)
      points1.remove(points1.size()-1);
    break; 

  case 1:
    if (points2.size()>0)
      points2.remove(points2.size()-1);
    break;

  case 2:
    if (points3.size()>0)
      points3.remove(points3.size()-1);
    break;

  case 3:
    if (points4.size()>0)
      points4.remove(points4.size()-1);
    break;
  }//switch
  //
}//func 
//

here

very small graphs

import processing.serial.*; 
import controlP5.*;   
import grafica.*;

Serial myPort;    // The serial port: 
ControlP5 controlP5;   // controlP5 object
Knob myKnob1, myKnob2, myKnob3, myKnob4;

ArrayList<PVector> points1 = new ArrayList(); // left one 
ArrayList<PVector> points2 = new ArrayList(); // right one

boolean activeArrayListIsLeft = true; 

boolean showHelpText1 = true; 

String inString;  // Input string from serial port: 
int lf = 10;      // ASCII linefeed 
float deg, val;

final String pathFolder="";//CARTELLA DI PERCORSO
final String fileExtension = ".txt";//estensione file
// unique numbers for constants: 
final int normal = 0;
final int save   = 1;
final int load   = 2;
///current state (must be one of them) 
/// stato attuale (deve essere uno di loro)
int state=normal;

// Paths 
String savePath=""; 
String loadPath=""; 
void setup() {
  size(1350, 750);

  // not necessary
  for (int i = 0; i < 3; i++) { 
    points1.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for

  // not necessary 
  for (int i = 0; i < 13; i++) { 
    points2.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for

  //ControlP5
  PFont  f= createFont ("Georgia", 25);
  {
    controlP5 = new ControlP5(this);   //ControlP5

    myKnob1 = controlP5.addKnob(" Massa ARIA")
      //.setRange(0,1024)
      .setRange(0, 5)
      .setValue(0)
      .setPosition(width-370, height-185)//posizione 605
      .setTickMarkLength(10)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //  . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      . setDecimalPrecision(2) //numero dopo la virgola
      ;
    myKnob1 .getCaptionLabel()
      . setFont(f);
    myKnob1.getValueLabel()
      .setFont(f)
      ;
    ;

    myKnob2 = controlP5.addKnob("P. Cil")
      .setRange(0, 500)
      .setValue(0)
      .setPosition(width-370, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      // . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      .  setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10) 
      ;
    myKnob2 .getCaptionLabel()
      . setFont(f);
    myKnob2.getValueLabel()
      .setFont(f)
      ;

    myKnob3 = controlP5.addKnob("P. Atm ")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob3 .getCaptionLabel()
      . setFont(f);
    myKnob3.getValueLabel()
      .setFont(f)
      ;

    myKnob4 = controlP5.addKnob("temp")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-185)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob4 .getCaptionLabel()
      . setFont(f);
    myKnob4.getValueLabel()
      .setFont(f)
      ;
  }
}
//  myPort = new Serial(this, "com3", 9600);  // ?????
//  myPort.bufferUntil(lf);
// }

void draw() {

  switch (state) {

  case normal:
    drawForStateNormal() ;
    break; 

  case save:
    // wait for Save Dialog 
    waitForSaveDialog();
    break; 

  case load:
    // wait for Load Dialog 
    waitForLoadDialog();
    break;

  default:
    //Error 
    println("Fail");
    exit();
    break; 
    //
  }//switch
}//func

// ------------------------------------------------

void drawForStateNormal() {

  background(245);
  {
    strokeWeight(2);   
    stroke(#FF0B03);
    fill(0);
    rect(width-380, height-490, 360, 90, 20);// retangolo diff. press.
    fill(255);
    textSize(28); 
    text("Diff.Press.", width-270, height-405);     //diff.press
    textSize(40);
    text(( myKnob2.getValue()- myKnob3.getValue()), width-270, height-445);     //diff.press
  }
  {
    fill(0);
    strokeWeight(2);   
    stroke(#FF0B03);

    rect(width-380, height-390, 360, 190, 20);// retangolo press
    rect(width-380, height-195, 360, 190, 20);// rettangolo massa Temp
  }
  textSize(14);
  showData1();
  showData2();

  // title 
  fill(255, 2, 2);
  text("My little Graph program\n\nUse buttons on the right and below;\n"    //testo e posizione testo
    +"use Backspace OR delete key to delete last data point of each list.", 
    width-223, 10, 100, 422);

  // help
  if (showHelpText1) {
    fill(255, 2, 2);
    text("Use 1 and 2 to set the active table which is marked by the horizontal line on top.\n\n"
      +"New, Load and Save are referring to the active table.\n\nHit x to hide / show this text.", 
      420, 10, 100, 422);
  }

  // ----------------------
  // buttons
  showButtons();
  //
} //draw

// --------------------------------------------------
// functions to show buttons funzione per mostrare i bottoni

void showButtons() {
  //
  strokeWeight(2);   
  stroke(0);
  textSize(15);
  fill(0);
  if ( overSave() ) {
    fill(#FF0303);
  }

  rect(width-50, height-740, 40, 20, 5);// modificato posizione bottone "salve"
  fill(255); 
  text("Save", 
    width-50+2, height-740+9+6);
  // ---
  fill(0);
  if ( overLoad() ) {
    fill(#49C3FA);
  }

  rect(width-50, height-710, 40, 20, 5);// modificato posizione" load"
  fill(255); 
  text("Load", 
    width-50+2, height-710+9+6);

  // ---
  fill(0);
  if ( overNew() ) {
    fill(#1FFF03);
  }

  rect(width-50, height-680, 40, 20, 5);// modificato posizione "new"
  fill(255); 
  text("New", 
    width-50+4, height-680+9+6);
}

//----------------------------------------------------------------------------
// functions to register if mouse is over buttons funzione da registrare se il mouse è sui pulsanti

boolean overSave() {            // modificato
  return mouseX > width-50 && 
    mouseY > height-740  && 
    mouseY < height-740+25 ;
}

boolean overLoad() {                 //modificato
  return mouseX > width-50 && 
    mouseY > height-710  && 
    mouseY < height-710+25 ;
}

boolean overNew() {                         //modificato
  return mouseX > width -50 && 
    mouseY > height-680  && 
    mouseY < height-680+25 ;
}

// ---------------------------------------------------------------------------
// Inputs 

void keyPressed() {

  if (state!=normal)
    return;

  //  
  if (  keyCode == BACKSPACE ) {
    //
    if (points1.size()>0)
      points1.remove(points1.size()-1);
  } 
  // ----
  if ( keyCode == DELETE ) {
    //
    if (points2.size()>0)
      points2.remove(points2.size()-1);
  } 

  // ------

  else {
    if ( key != CODED ) {
      //
      switch(key) {

      case '1':
        activeArrayListIsLeft = true; 
        break;

      case '2':
        activeArrayListIsLeft = false; 
        break;

      case 'x':
        showHelpText1 = !showHelpText1; 
        break;
      }//switch
      //
    }//if
  }//else
}// func 

void mousePressed() {

  if (state!=normal)
    return;

  // for the buttons 
  if ( overSave() ) {
    initSave();
  }
  //---
  else if ( overLoad() ) {
    initLoad();
  }
  //---
  else if ( overNew() ) {
    //
    if ( activeArrayListIsLeft ) {
      points1.clear();            //cancellare punti con new
      //  not necessary:
      for (int i = 0; i < 13; i++) { 
        // points1.add(new PVector(i, 20 + 10*noise(i*0.1)));
      }//for
    } else {
      points2.clear();            //cancellare punti con new
      //  not necessary:
      for (int i = 0; i < 13; i++) { 
        // points2.add(new PVector(i, 20 + 10*noise(i*0.1)));
      }//for
    }
    //
  }
  //---
  else {
    // points.add(new PVector(points.size(), mouseY/10));
    if ( activeArrayListIsLeft ) {
      // points1.add(new PVector(points1.size(), myKnob1.getValue()));
      points1.add(new PVector(points1.size(), mouseY));
    } else {

      //points2.add(new PVector(points2.size(), myKnob1.getValue()));
      points2.add(new PVector(points2.size(), mouseY));
    }
  }
}//func

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath="";
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-"
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2);
  // prepare fileDescription which occurs in the dialogue
  // prepara la descrizione del file che avviene nel dialogo
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//"
    + dateTimeStamp
    + fileExtension);
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription);
  // set state to wait
  state=save;
}

void initLoad() {
  // init load process 
  // reset
  loadPath="";
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension );
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription);
  // set state to wait
  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");


    // println ("La finestra è stata chiusa o l'utente ha premuto annulla.");
    // torna indietro

    state=normal;    // go back
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");

    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt();
    // go back 
    state=normal;
  }
}

void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt();
    // go back 
    state=normal;
  }
}

void saveIt() {
  // save

  // make array (to save it)

  String[] strs; 

  if (activeArrayListIsLeft) {
    strs = new String[points1.size()];
    int i=0;
    for (PVector pv : points1) {
      strs[i]=str(pv.x)+","+str(pv.y);
      i++;
    }//for
  }// 
  else {
    strs = new String[points2.size()];
    int i=0;
    for (PVector pv : points2) {
      strs[i]=str(pv.x)+","+str(pv.y);
      i++;
    }//for
  }//else 

  // check if file extension (fileExtension, e.g. .txt) is there 
  int len = savePath.length(); 
  if (len<4 || !savePath.substring( len-4 ).equals(fileExtension)) {
    // file Extension is not present, we have to add it
    savePath += fileExtension; // add the file Extension
  } 

  // save 
  println("Saved: " + savePath);
  saveStrings( savePath, strs );
}//func

void loadIt() {
  // load
  if (activeArrayListIsLeft) {
    points1.clear();
  } else 
  {
    points2.clear();
  }
  String[] strs = loadStrings( loadPath );
  for (String s : strs) {
    String[] thisLine=split(s, ",");

    if (activeArrayListIsLeft) {
      points1.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    } else 
    {
      points2.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    }//else 
    //
  }//for
}

// -------------------------------------------------

void showData1() {
  //
  // show data LEFT 
  PVector prev = new PVector(-1, -1); 
  int y=50; 

  if (activeArrayListIsLeft) {
    stroke(255, 2, 2); // RED
    line (10, 10, 198, 10);
  }

  for (PVector pv : points1) {

    fill(255, 2, 2); // RED 

    // show data
    text(pv.x, 30, y); 
    text(pv.y, 110, y);

    fill(0, 2, 2); 
    stroke(255, 2, 2); // RED 
    float yvalue = map( pv.y, 0, height, 300, 355);
    if (prev.x!=-1) {
      line(10 + pv.x*3, yvalue, 
        prev.x, prev.y);
    }
    noStroke();
    // ellipse (10 + pv.x*3, yvalue, 4, 4);
    prev = new PVector(10 + pv.x*3, yvalue); 

    y+=20; //next line
  }//for

  // middle line 
  stroke(255, 2, 2); // RED 
  line( 100, 30, 100, height);

  // double middle lines!!!   ???
  stroke(0); // BLACK 
  int x1=200;
  line( x1-2, 30, x1-2, height);
  line( x1+2, 30, x1+2, height);
  //
}

void showData2() {
  //
  // show data RIGHT 

  if (!activeArrayListIsLeft) {
    // activeArrayListIsLeft is FALSE, right side is active
    stroke(2, 255, 2); // GREEN
    line (200, 10, 
      350, 10);
  }

  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points2) {

    fill(0, 255, 2); // GREEN 

    // show data
    text(pv.x, 210, y); 
    text(pv.y, 290, y);

    fill(0, 2, 2); 
    stroke(0, 255, 2); // GREEN 
    float yvalue = map( pv.y, 0, height, 300, 355);
    if (prev.x!=-1) {
      line(10 + pv.x*3, yvalue, 
        prev.x, prev.y);
    }
    noStroke();
    //   ellipse (10 + pv.x*3, yvalue, 4, 4);
    prev = new PVector(10 + pv.x*3, yvalue); 

    y+=20; //next line
  }//for

  // middle line 
  stroke(0, 255, 2); // GREEN 
  line( 288, 30, 288, height);
  //
}

// ---------------------------------------------------------------

void serialEvent(Serial p) { 
  inString = p.readString(); 
  char primo=inString.charAt(0);  // primo carattere
  String cifra=inString.substring(1);  // da secondo carattere in poi
  float val=parseFloat(cifra);          // valore da 0-255 o 0-1023, non sò cosa spedisce arduino


  print("val=");    
  println(val);

  //   inString = trim(inString);

  //    // converte in int e mappa all'altezza dello schermo: 


  switch(primo) { 
    case ('A'): 
    myKnob1.setValue(val);
    break;
    case ('B'): 
    myKnob2.setValue(val);
    break;
    case ('C'): 
    myKnob3.setValue(val);
    break;
    case ('D'): 
    myKnob3.setValue(val);
    break;
  }
}

Basically I am very new to this android mode i tried SelectInput from Processing reference and also tried Select Library for android mode Non of them seem to work .

i want to load images from device in my sketch and use the Pixel RGB Values using get(x,y); and perform certain process on image in Android device.

i need Help in selecting Image file from Android Device Gallery Cheers

Hi, I am very new to this android mode i tried SelectInput from Processing reference and also tried Select Library for android mode Non of them seem to work .

i want to load images from device in my sketch and use the Pixel RGB Values using get(x,y); and perform certain process on image in Android device.

i need Help in selecting Image file from Android Device Gallery :D Cheers

This is what I have in mind, but I have not succeeded yet .... Point1 and Point2 I would like to draw in the GPlot chart .... import processing.serial.*; import controlP5.*;
import grafica.*;

Serial myPort;    // The serial port: 
ControlP5 controlP5;   // controlP5 object
Knob myKnob1, myKnob2, myKnob3, myKnob4;

ArrayList<PVector> points1 = new ArrayList(); // left one 
ArrayList<PVector> points2 = new ArrayList(); // right one

boolean activeArrayListIsLeft = true; 

boolean showHelpText1 = true; 

String inString;  // Input string from serial port: 
int lf = 10;      // ASCII linefeed 
float deg, val;

final String pathFolder="";//CARTELLA DI PERCORSO
final String fileExtension = ".txt";//estensione file
// unique numbers for constants: 
final int normal = 0;
final int save   = 1;
final int load   = 2;
///current state (must be one of them) 

int state=normal;

// Paths 
String savePath=""; 
String loadPath=""; 

GPlot plot;
int xPos=0;
void setup() {
  size(1350, 750);

  // not necessary
  for (int i = 0; i < 3; i++) { 
    points1.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for

  // not necessary 
  for (int i = 0; i < 13; i++) { 
    points2.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for

  //ControlP5
  PFont  f= createFont ("Georgia", 25);
  {
    controlP5 = new ControlP5(this);   //ControlP5

    myKnob1 = controlP5.addKnob(" Massa ARIA")
      //.setRange(0,1024)
      .setRange(0, 5)
      .setValue(0)
      .setPosition(width-370, height-185)//posizione 605
      .setTickMarkLength(10)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //  . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      . setDecimalPrecision(2) //numero dopo la virgola
      ;
    myKnob1 .getCaptionLabel()
      . setFont(f);
    myKnob1.getValueLabel()
      .setFont(f)
      ;
    ;

    myKnob2 = controlP5.addKnob("P. Cil")
      .setRange(0, 500)
      .setValue(0)
      .setPosition(width-370, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      // . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      .  setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10) 
      ;
    myKnob2 .getCaptionLabel()
      . setFont(f);
    myKnob2.getValueLabel()
      .setFont(f)
      ;

    myKnob3 = controlP5.addKnob("P. Atm ")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob3 .getCaptionLabel()
      . setFont(f);
    myKnob3.getValueLabel()
      .setFont(f)
      ;

    myKnob4 = controlP5.addKnob("temp")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-185)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob4 .getCaptionLabel()
      . setFont(f);
    myKnob4.getValueLabel()
      .setFont(f)
      ;
  }
}
//  myPort = new Serial(this, "com3", 9600);  // ?????
//  myPort.bufferUntil(lf);
// }
{
   // Create the first plot  Crea il primo grafico
 plot = new GPlot(this);
  plot.setPos(200,200);//posizione
  plot.setMar(0, 100, 0,100);
  plot.setDim(1000, 480);//dimensione
  plot.setAxesOffset(4);
  plot.setTicksLength(4);



  int myKnob1 =0;
  GPointsArray points = new GPointsArray(myKnob1);

  for (int i = 0; i < 13; i++) {
   //points.add(i, 20 + 10*noise(i*0.1));
    if(xPos==13){
    }
    {

  // Set the points, the title and the axis labels 
  plot.setPoints(points);
  plot.getYAxis().setAxisLabelText("y(?)");
  plot.getXAxis().setAxisLabelText("x (?)");
    }
  }
}


void draw() {

  // Draw the first plot
  //Disegna la prima trama 
  plot.beginDraw();
  plot.drawBox();
  plot.drawXAxis();
  plot.drawYAxis();
  plot.drawTitle();
 //plot1.drawPoints();//pallinorosso sul valore
  plot.drawGridLines(GPlot.BOTH);
  plot.drawLines();
  plot.endDraw();
}
{

  switch (state) {

  case normal:
    drawForStateNormal() ;
    break; 

  case save:
    // wait for Save Dialog 
    waitForSaveDialog();
    break; 

  case load:
    // wait for Load Dialog 
    waitForLoadDialog();
    break;

  default:
    //Error 
    println("Fail");
    exit();
    break; 
    //
  }//switch
}//func

void drawForStateNormal() {

  background(245);
  {
    strokeWeight(2);   
    stroke(#FF0B03);
    fill(0);
    rect(width-380, height-490, 360, 90, 20);// retangolo diff. press.
    fill(255);
    textSize(28); 
    text("Diff.Press.", width-270, height-405);     //diff.press
    textSize(40);
    text(( myKnob2.getValue()- myKnob3.getValue()), width-270, height-445);     //diff.press
  }
  {
    fill(0);
    strokeWeight(2);   
    stroke(#FF0B03);

    rect(width-380, height-390, 360, 190, 20);// retangolo press
    rect(width-380, height-195, 360, 190, 20);// rettangolo massa Temp
  }
  textSize(14);
  showData1();
  showData2();

  // title 
  fill(255, 2, 2);
  text("My little Graph program\n\nUse buttons on the right and below;\n"    //testo e posizione testo
    +"use Backspace OR delete key to delete last data point of each list.", 
    width-223, 10, 100, 422);

  // help
  if (showHelpText1) {
    fill(255, 2, 2);
    text("Use 1 and 2 to set the active table which is marked by the horizontal line on top.\n\n"
      +"New, Load and Save are referring to the active table.\n\nHit x to hide / show this text.", 
      420, 10, 100, 422);

  }

  // buttons
  showButtons();
  //
} //draw

// functions to show buttons funzione per mostrare i bottoni

void showButtons() {
  //
  strokeWeight(2);   
  stroke(0);
  textSize(15);
  fill(0);
  if ( overSave() ) {
    fill(#FF0303);
  }

  rect(width-50, height-740, 40, 20, 5);// modificato posizione bottone "salve"
  fill(255); 
  text("Save", 
    width-50+2, height-740+9+6);
  // ---
  fill(0);
  if ( overLoad() ) {
    fill(#49C3FA);
  }

  rect(width-50, height-710, 40, 20, 5);// modificato posizione" load"
  fill(255); 
  text("Load", 
    width-50+2, height-710+9+6);

  // ---
  fill(0);
  if ( overNew() ) {
    fill(#1FFF03);
  }

  rect(width-50, height-680, 40, 20, 5);// modificato posizione "new"
  fill(255); 
  text("New", 
    width-50+4, height-680+9+6);
}

// functions to register if mouse is over buttons funzione da registrare se il mouse è sui pulsanti

boolean overSave() {            // modificato
  return mouseX > width-50 && 
    mouseY > height-740  && 
    mouseY < height-740+25 ;
}

boolean overLoad() {                 //modificato
  return mouseX > width-50 && 
    mouseY > height-710  && 
    mouseY < height-710+25 ;
}

boolean overNew() {                         //modificato
  return mouseX > width -50 && 
    mouseY > height-680  && 
    mouseY < height-680+25 ;
}

// Inputs 

void keyPressed() {

  if (state!=normal)
    return;

  //  
  if (  keyCode == BACKSPACE ) {          //da controllare non funziona
    //
    if (points1.size()>0)
      points1.remove(points1.size()-1);
  } 
  // ----
  if ( keyCode == DELETE ) {
    //
    if (points2.size()>0)
      points2.remove(points2.size()-1);
  } 

  // ------

  else {
    if ( key != CODED ) {
      //
      switch(key) {

      case '1':
        activeArrayListIsLeft = true; 
        break;

      case '2':
        activeArrayListIsLeft = false; 
        break;

      case 'x':
        showHelpText1 = !showHelpText1; 
        break;
      }//switch
      //
    }//if
  }//else
}// func 

void mousePressed() {

  if (state!=normal)
    return;

  // for the buttons 
  if ( overSave() ) {
    initSave();
  }
  //---
  else if ( overLoad() ) {
    initLoad();
  }
  //---
  else if ( overNew() ) {
    //
    if ( activeArrayListIsLeft ) {
      points1.clear();            //cancellare punti con new
      //  not necessary:
      for (int i = 0; i < 13; i++) { 
        // points1.add(new PVector(i, 20 + 10*noise(i*0.1)));
      }//for
    } else {
      points2.clear();            //cancellare punti con new
      //  not necessary:
      for (int i = 0; i < 13; i++) { 
        // points2.add(new PVector(i, 20 + 10*noise(i*0.1)));
      }//for
    }
    //
  }
  //---
  else {
    // points.add(new PVector(points.size(), mouseY/10));
    if ( activeArrayListIsLeft ) {
      points1.add(new PVector(points1.size(), myKnob1.getValue()));
    } else {
      points2.add(new PVector(points2.size(), myKnob1.getValue()));
    }
  }
}//func

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath="";
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
 2 diventa 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-"
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2);
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//"
    + dateTimeStamp
    + fileExtension);
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription);
  // set state to wait
  state=save;

   GPoint lastPoint = plot.getPointsRef().getLastPoint();

  if (lastPoint == null) {

       plot.addPoint(xPos, +myKnob1.getValue(), "(" + str(xPos) + " , " + str(myKnob1.getValue()) + ")");

  } 
  else if (!lastPoint.isValid() || sq(lastPoint.getX() - xPos) + sq(lastPoint.getY() + myKnob1.getValue()) > 2500) {
    //plot1.addPoint(xPos, -val, "(" + (xPos) + " , " + (-val) + ")");


  }

  // Reset the points if the user pressed the space bar
  if (keyPressed && key == ' ') {
    plot.setPoints(new GPointsArray());
  }
}

void initLoad() {
  // init load process 
  // reset
  loadPath="";
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension );
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription);
  // set state to wait

  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");

    state=normal;    // go back
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");

    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt();
    // go back 
    state=normal;
  }
}

void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt();
    // go back 
    state=normal;
  }
}

void saveIt() {
  // save

  // make array (to save it)

  String[] strs; 

  if (activeArrayListIsLeft) {
    strs = new String[points1.size()];
    int i=0;
    for (PVector pv : points1) {
      strs[i]=str(pv.x)+","+str(pv.y);
      i++;
    }//for
  }// 
  else {
    strs = new String[points2.size()];
    int i=0;
    for (PVector pv : points2) {
      strs[i]=str(pv.x)+","+str(pv.y);
      i++;
    }//for
  }//else 

  // check if file extension (fileExtension, e.g. .txt) is there 
  int len = savePath.length(); 
  if (len<4 || !savePath.substring( len-4 ).equals(fileExtension)) {
    // file Extension is not present, we have to add it
    savePath += fileExtension; // add the file Extension
  } 

  // save 
  println("Saved: " + savePath);
  saveStrings( savePath, strs );
}//func

void loadIt() {
  // load
  if (activeArrayListIsLeft) {
    points1.clear();
  } else
  {
    points2.clear();
  }
  String[] strs = loadStrings( loadPath );
  for (String s : strs) {
    String[] thisLine=split(s, ",");

    if (activeArrayListIsLeft) {
      points1.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    } else
    {
      points2.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    }//else 
    //
  }//for
}

void showData1() {
  //
  // show data LEFT 
  PVector prev = new PVector(-1, -1); 
  int y=50; 

  if (activeArrayListIsLeft) {
    stroke(255, 2, 2); // RED
    line (10, 10, 198, 10);
  }

  for (PVector pv : points1) {

    fill(255, 2, 2); // RED 

    // show data
    text(pv.x, 30, y); 
    text(pv.y, 110, y);

    fill(0, 2, 2); 
    stroke(255, 2, 2); // RED 
    if (prev.x!=-1) {
      line(10 + pv.x*30, pv.y*10, 
        prev.x, prev.y);
    }
    noStroke();
    ellipse (10 + pv.x*30, pv.y*10, 4, 4);
    prev = new PVector(10 + pv.x*30, pv.y*10); 

    y+=20; //next line
  }//for

  // middle line 
  stroke(255, 2, 2); // RED 
  line( 100, 30, 100, height);

  // double middle lines!!!   ???
  stroke(0); // BLACK 
  int x1=200;
  line( x1-2, 30, x1-2, height);
  line( x1+2, 30, x1+2, height);
  //
 }

  void showData2() {
  //
  // show data RIGHT 

  if (!activeArrayListIsLeft) {
    // activeArrayListIsLeft is FALSE, right side is active

   // activeArrayListIsLeft è FALSE, il lato destro è attivo
    stroke(2, 255, 2); // GREEN
    line (200, 10, 
      350, 10);
  }

  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points2) {

    fill(0, 255, 2); // GREEN 

    // show data
    text(pv.x, 210, y); 
    text(pv.y, 290, y);

    fill(0, 2, 2); 
    stroke(0, 255, 2); // GREEN 
    if (prev.x!=-1) {
      line(10 + pv.x*30, pv.y*10, 
        prev.x, prev.y);
    }
    noStroke();
    ellipse (10 + pv.x*30, pv.y*10, 4, 4);
    prev = new PVector(10 + pv.x*30, pv.y*10); 

    y+=20; //next line
  }//for

  // middle line 
  stroke(0, 255, 2); // GREEN 
  line( 288, 30, 288, height);
  //
 }


 void serialEvent(Serial p) { 
  inString = p.readString(); 
  char primo=inString.charAt(0);  // primo carattere
  String cifra=inString.substring(1);  // da secondo carattere in poi
  float val=parseFloat(cifra);          // valore da 0-255 o 0-1023, non sò cosa 
  print("val=");    
  println(val);
  switch(primo) { 
    case ('A'): 
    myKnob1.setValue(val);
    break;
    case ('B'): 
    myKnob2.setValue(val);
    break;
    case ('C'): 
    myKnob3.setValue(val);
    break;
    case ('D'): 
    myKnob3.setValue(val);
    break;
  }

}

new version with 2 tables and graphs.

• Delete key and Backspace key are now referring to the different tables separately

• Use key 1 and 2 to set the active table

• New, Load and Save are referring to the active table.

• Hit x to hide / show help text

Chrisir ;-)

import processing.serial.*; 
import controlP5.*;   
import grafica.*;

Serial myPort;    // The serial port: 
ControlP5 controlP5;   // controlP5 object
Knob myKnob1, myKnob2, myKnob3, myKnob4;

ArrayList<PVector> points1 = new ArrayList(); // left one 
ArrayList<PVector> points2 = new ArrayList(); // right one

boolean activeArrayListIsLeft = true; 

boolean showHelpText1 = true; 

String inString;  // Input string from serial port: 
int lf = 10;      // ASCII linefeed 
float deg, val;

final String pathFolder="";//CARTELLA DI PERCORSO
final String fileExtension = ".txt";//estensione file
// unique numbers for constants: 
final int normal = 0;
final int save   = 1;
final int load   = 2;
///current state (must be one of them) 
/// stato attuale (deve essere uno di loro)
int state=normal;

// Paths 
String savePath=""; 
String loadPath=""; 
void setup() {
  size(1350, 750);

  // not necessary
  for (int i = 0; i < 3; i++) { 
    points1.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for

  // not necessary 
  for (int i = 0; i < 13; i++) { 
    points2.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for

  //ControlP5
  PFont  f= createFont ("Georgia", 25);
  {
    controlP5 = new ControlP5(this);   //ControlP5

    myKnob1 = controlP5.addKnob(" Massa ARIA")
      //.setRange(0,1024)
      .setRange(0, 5)
      .setValue(0)
      .setPosition(width-370, height-185)//posizione 605
      .setTickMarkLength(10)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //  . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      . setDecimalPrecision(2) //numero dopo la virgola
      ;
    myKnob1 .getCaptionLabel()
      . setFont(f);
    myKnob1.getValueLabel()
      .setFont(f)
      ;
    ;

    myKnob2 = controlP5.addKnob("P. Cil")
      .setRange(0, 500)
      .setValue(0)
      .setPosition(width-370, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      // . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      // .setScrollSensitivity(120)
      .  setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10) 
      ;
    myKnob2 .getCaptionLabel()
      . setFont(f);
    myKnob2.getValueLabel()
      .setFont(f)
      ;

    myKnob3 = controlP5.addKnob("P. Atm ")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-380)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob3 .getCaptionLabel()
      . setFont(f);
    myKnob3.getValueLabel()
      .setFont(f)
      ;

    myKnob4 = controlP5.addKnob("temp")
      //.setRange(0,1023)
      .setRange(0, 500)
      .setValue(1)
      .setPosition(width-180, height-185)
      .setColorForeground(color(#FF0004))//colore cursore
      .setColorBackground(color(255))//colore sfondo
      .setColorValueLabel(color(0))//colore numeri//label etichetta
      .setColorActive(color(#6AFA05))
      .setDragDirection(Knob.VERTICAL)
      //   . setColorCaptionLabel(0) //colore scritta(capition)
      .lock()
      .setSize(150, 150)//dimensioni
      .setDecimalPrecision(2) //numero dopo la virgola
      .setTickMarkLength(10)
      ;
    myKnob4 .getCaptionLabel()
      . setFont(f);
    myKnob4.getValueLabel()
      .setFont(f)
      ;
  }
}
//  myPort = new Serial(this, "com3", 9600);  // ?????
//  myPort.bufferUntil(lf);
// }

void draw() {

  switch (state) {

  case normal:
    drawForStateNormal() ;
    break; 

  case save:
    // wait for Save Dialog 
    waitForSaveDialog();
    break; 

  case load:
    // wait for Load Dialog 
    waitForLoadDialog();
    break;

  default:
    //Error 
    println("Fail");
    exit();
    break; 
    //
  }//switch
}//func

// ------------------------------------------------

void drawForStateNormal() {

  background(245);
  {
    strokeWeight(2);   
    stroke(#FF0B03);
    fill(0);
    rect(width-380, height-490, 360, 90, 20);// retangolo diff. press.
    fill(255);
    textSize(28); 
    text("Diff.Press.", width-270, height-405);     //diff.press
    textSize(40);
    text(( myKnob2.getValue()- myKnob3.getValue()), width-270, height-445);     //diff.press
  }
  {
    fill(0);
    strokeWeight(2);   
    stroke(#FF0B03);

    rect(width-380, height-390, 360, 190, 20);// retangolo press
    rect(width-380, height-195, 360, 190, 20);// rettangolo massa Temp
  }
  textSize(14);
  showData1();
  showData2();

  // title 
  fill(255, 2, 2);
  text("My little Graph program\n\nUse buttons on the right and below;\n"    //testo e posizione testo
    +"use Backspace OR delete key to delete last data point of each list.", 
    width-223, 10, 100, 422);

  // help
  if (showHelpText1) {
    fill(255, 2, 2);
    text("Use 1 and 2 to set the active table which is marked by the horizontal line on top.\n\n"
      +"New, Load and Save are referring to the active table.\n\nHit x to hide / show this text.", 
      420, 10, 100, 422);
  }

  // ----------------------
  // buttons
  showButtons();
  //
} //draw

// --------------------------------------------------
// functions to show buttons funzione per mostrare i bottoni

void showButtons() {
  //
  strokeWeight(2);   
  stroke(0);
  textSize(15);
  fill(0);
  if ( overSave() ) {
    fill(#FF0303);
  }

  rect(width-50, height-740, 40, 20, 5);// modificato posizione bottone "salve"
  fill(255); 
  text("Save", 
    width-50+2, height-740+9+6);
  // ---
  fill(0);
  if ( overLoad() ) {
    fill(#49C3FA);
  }

  rect(width-50, height-710, 40, 20, 5);// modificato posizione" load"
  fill(255); 
  text("Load", 
    width-50+2, height-710+9+6);

  // ---
  fill(0);
  if ( overNew() ) {
    fill(#1FFF03);
  }

  rect(width-50, height-680, 40, 20, 5);// modificato posizione "new"
  fill(255); 
  text("New", 
    width-50+4, height-680+9+6);
}

//----------------------------------------------------------------------------
// functions to register if mouse is over buttons funzione da registrare se il mouse è sui pulsanti

boolean overSave() {            // modificato
  return mouseX > width-50 && 
    mouseY > height-740  && 
    mouseY < height-740+25 ;
}

boolean overLoad() {                 //modificato
  return mouseX > width-50 && 
    mouseY > height-710  && 
    mouseY < height-710+25 ;
}

boolean overNew() {                         //modificato
  return mouseX > width -50 && 
    mouseY > height-680  && 
    mouseY < height-680+25 ;
}

// ---------------------------------------------------------------------------
// Inputs 

void keyPressed() {

  if (state!=normal)
    return;

  //  
  if (  keyCode == BACKSPACE ) {
    //
    if (points1.size()>0)
      points1.remove(points1.size()-1);
  } 
  // ----
  if ( keyCode == DELETE ) {
    //
    if (points2.size()>0)
      points2.remove(points2.size()-1);
  } 

  // ------

  else {
    if ( key != CODED ) {
      //
      switch(key) {

      case '1':
        activeArrayListIsLeft = true; 
        break;

      case '2':
        activeArrayListIsLeft = false; 
        break;

      case 'x':
        showHelpText1 = !showHelpText1; 
        break;
      }//switch
      //
    }//if
  }//else
}// func 

void mousePressed() {

  if (state!=normal)
    return;

  // for the buttons 
  if ( overSave() ) {
    initSave();
  }
  //---
  else if ( overLoad() ) {
    initLoad();
  }
  //---
  else if ( overNew() ) {
    //
    if ( activeArrayListIsLeft ) {
      points1.clear();            //cancellare punti con new
      //  not necessary:
      for (int i = 0; i < 13; i++) { 
        // points1.add(new PVector(i, 20 + 10*noise(i*0.1)));
      }//for
    } else {
      points2.clear();            //cancellare punti con new
      //  not necessary:
      for (int i = 0; i < 13; i++) { 
        // points2.add(new PVector(i, 20 + 10*noise(i*0.1)));
      }//for
    }
    //
  }
  //---
  else {
    // points.add(new PVector(points.size(), mouseY/10));
    if ( activeArrayListIsLeft ) {
      points1.add(new PVector(points1.size(), myKnob1.getValue()));
    } else {
      points2.add(new PVector(points2.size(), myKnob1.getValue()));
    }
  }
}//func

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath="";
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-"
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2);
  // prepare fileDescription which occurs in the dialogue
  // prepara la descrizione del file che avviene nel dialogo
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//"
    + dateTimeStamp
    + fileExtension);
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription);
  // set state to wait
  state=save;
}

void initLoad() {
  // init load process 
  // reset
  loadPath="";
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension );
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription);
  // set state to wait
  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");


    // println ("La finestra è stata chiusa o l'utente ha premuto annulla.");
    // torna indietro

    state=normal;    // go back
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");

    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt();
    // go back 
    state=normal;
  }
}

void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt();
    // go back 
    state=normal;
  }
}

void saveIt() {
  // save

  // make array (to save it)

  String[] strs; 

  if (activeArrayListIsLeft) {
    strs = new String[points1.size()];
    int i=0;
    for (PVector pv : points1) {
      strs[i]=str(pv.x)+","+str(pv.y);
      i++;
    }//for
  }// 
  else {
    strs = new String[points2.size()];
    int i=0;
    for (PVector pv : points2) {
      strs[i]=str(pv.x)+","+str(pv.y);
      i++;
    }//for
  }//else 

  // check if file extension (fileExtension, e.g. .txt) is there 
  int len = savePath.length(); 
  if (len<4 || !savePath.substring( len-4 ).equals(fileExtension)) {
    // file Extension is not present, we have to add it
    savePath += fileExtension; // add the file Extension
  } 

  // save 
  println("Saved: " + savePath);
  saveStrings( savePath, strs );
}//func

void loadIt() {
  // load
  if (activeArrayListIsLeft) {
    points1.clear();
  } else 
  {
    points2.clear();
  }
  String[] strs = loadStrings( loadPath );
  for (String s : strs) {
    String[] thisLine=split(s, ",");

    if (activeArrayListIsLeft) {
      points1.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    } else 
    {
      points2.add(new PVector(float(thisLine[0]), float(thisLine[1])));
    }//else 
    //
  }//for
}

// -------------------------------------------------

void showData1() {
  //
  // show data LEFT 
  PVector prev = new PVector(-1, -1); 
  int y=50; 

  if (activeArrayListIsLeft) {
    stroke(255, 2, 2); // RED
    line (10, 10, 198, 10);
  }

  for (PVector pv : points1) {

    fill(255, 2, 2); // RED 

    // show data
    text(pv.x, 30, y); 
    text(pv.y, 110, y);

    fill(0, 2, 2); 
    stroke(255, 2, 2); // RED 
    if (prev.x!=-1) {
      line(10 + pv.x*30, pv.y*10, 
        prev.x, prev.y);
    }
    noStroke();
    ellipse (10 + pv.x*30, pv.y*10, 4, 4);
    prev = new PVector(10 + pv.x*30, pv.y*10); 

    y+=20; //next line
  }//for

  // middle line 
  stroke(255, 2, 2); // RED 
  line( 100, 30, 100, height);

  // double middle lines!!!   ???
  stroke(0); // BLACK 
  int x1=200;
  line( x1-2, 30, x1-2, height);
  line( x1+2, 30, x1+2, height);
  //
}

void showData2() {
  //
  // show data RIGHT 

  if (!activeArrayListIsLeft) {
    // activeArrayListIsLeft is FALSE, right side is active
    stroke(2, 255, 2); // GREEN
    line (200, 10, 
      350, 10);
  }

  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points2) {

    fill(0, 255, 2); // GREEN 

    // show data
    text(pv.x, 210, y); 
    text(pv.y, 290, y);

    fill(0, 2, 2); 
    stroke(0, 255, 2); // GREEN 
    if (prev.x!=-1) {
      line(10 + pv.x*30, pv.y*10, 
        prev.x, prev.y);
    }
    noStroke();
    ellipse (10 + pv.x*30, pv.y*10, 4, 4);
    prev = new PVector(10 + pv.x*30, pv.y*10); 

    y+=20; //next line
  }//for

  // middle line 
  stroke(0, 255, 2); // GREEN 
  line( 288, 30, 288, height);
  //
}

// ---------------------------------------------------------------

void serialEvent(Serial p) { 
  inString = p.readString(); 
  char primo=inString.charAt(0);  // primo carattere
  String cifra=inString.substring(1);  // da secondo carattere in poi
  float val=parseFloat(cifra);          // valore da 0-255 o 0-1023, non sò cosa spedisce arduino


  print("val=");    
  println(val);

  //   inString = trim(inString);

  //    // converte in int e mappa all'altezza dello schermo: 


  switch(primo) { 
    case ('A'): 
    myKnob1.setValue(val);
    break;
    case ('B'): 
    myKnob2.setValue(val);
    break;
    case ('C'): 
    myKnob3.setValue(val);
    break;
    case ('D'): 
    myKnob3.setValue(val);
    break;
  }
}

what do you think about it? I still do not understand how to draw the graph (y axis values ​​read via Arduino and x axis scales from 0 to 13 where each mouse pressed advances by 1) and relative table. And the part that I think very complicated to achieve, recall a previously saved Array List and be able to superimpose it on the chart (line of another color) and add it to the table just created .........

import processing.serial.*; 
import controlP5.*;   
import grafica.*;

Serial myPort;    // The serial port: 
ControlP5 controlP5;   // controlP5 object
Knob myKnob1,myKnob2,myKnob3,myKnob4;

ArrayList<PVector> points = new ArrayList();
String inString;  // Input string from serial port: 
int lf = 10;      // ASCII linefeed 
float deg, val;

final String pathFolder="";//CARTELLA DI PERCORSO
final String fileExtension = ".txt";//estensione file
// unique numbers for constants: 
final int normal = 0;
final int save   = 1;
final int load   = 2;
///current state (must be one of them) 
/// stato attuale (deve essere uno di loro)
int state=normal;

// Paths 
String savePath=""; 
String loadPath=""; 
 void setup() {
  size(1350, 750);

  // not necessary
  for (int i = 0; i < 3; i++) { 
    points.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for



  //ControlP5
  PFont  f= createFont ("Georgia", 25);
  {
  controlP5 = new ControlP5(this);   //ControlP5

  myKnob1 = controlP5.addKnob(" Massa ARIA")
             //.setRange(0,1024)
               .setRange(0,5)
               .setValue(0)
               .setPosition(width-370,height-185)//posizione 605
               .setTickMarkLength(10)
               .setColorForeground(color(#FF0004))//colore cursore
               .setColorBackground(color(255))//colore sfondo
               .setColorValueLabel(color(0))//colore numeri//label etichetta
               .setColorActive(color(#6AFA05))
               .setDragDirection(Knob.VERTICAL)
            //  . setColorCaptionLabel(0) //colore scritta(capition)
               .lock()
               .setSize(150,150)//dimensioni
             // .setScrollSensitivity(120)
               . setDecimalPrecision(2) //numero dopo la virgola
               ;
              myKnob1 .getCaptionLabel()
               . setFont(f);
              myKnob1.getValueLabel()
               .setFont(f)
               ;




                  ;
  myKnob2 = controlP5.addKnob("P. Cil")

               .setRange(0,500)
               .setValue(0)
               .setPosition(width-370,height-380)
                .setColorForeground(color(#FF0004))//colore cursore
               .setColorBackground(color(255))//colore sfondo
               .setColorValueLabel(color(0))//colore numeri//label etichetta
               .setColorActive(color(#6AFA05))
               .setDragDirection(Knob.VERTICAL)
              // . setColorCaptionLabel(0) //colore scritta(capition)
               .lock()
               .setSize(150,150)//dimensioni
             // .setScrollSensitivity(120)
                .  setDecimalPrecision(2) //numero dopo la virgola
                .setTickMarkLength(10) 
               ;
               myKnob2 .getCaptionLabel()
                . setFont(f);
               myKnob2.getValueLabel()
                .setFont(f)
               ;

  myKnob3 = controlP5.addKnob("P. Atm ")
               //.setRange(0,1023)
               .setRange(0,500)
               .setValue(1)
               .setPosition(width-180,height-380)
                .setColorForeground(color(#FF0004))//colore cursore
               .setColorBackground(color(255))//colore sfondo
               .setColorValueLabel(color(0))//colore numeri//label etichetta
               .setColorActive(color(#6AFA05))
               .setDragDirection(Knob.VERTICAL)
            //   . setColorCaptionLabel(0) //colore scritta(capition)
              .lock()
              .setSize(150,150)//dimensioni
              .setDecimalPrecision(2) //numero dopo la virgola
               .setTickMarkLength(10)
               ;
              myKnob3 .getCaptionLabel()
               . setFont(f);
              myKnob3.getValueLabel()
             .setFont(f)

               ;

                myKnob4 = controlP5.addKnob("temp")
               //.setRange(0,1023)
               .setRange(0,500)
               .setValue(1)
               .setPosition(width-180,height-185)
                .setColorForeground(color(#FF0004))//colore cursore
               .setColorBackground(color(255))//colore sfondo
               .setColorValueLabel(color(0))//colore numeri//label etichetta
               .setColorActive(color(#6AFA05))
               .setDragDirection(Knob.VERTICAL)
            //   . setColorCaptionLabel(0) //colore scritta(capition)
              .lock()
              .setSize(150,150)//dimensioni
              .setDecimalPrecision(2) //numero dopo la virgola
               .setTickMarkLength(10)
               ;
              myKnob4 .getCaptionLabel()
               . setFont(f);
              myKnob4.getValueLabel()
             .setFont(f)
              ;
            }
  }







//  myPort = new Serial(this, "com3", 9600);
//  myPort.bufferUntil(lf);
// }
 void draw() {


  switch (state) {

  case normal:
    drawForStateNormal() ;
    break; 

  case save:
    // wait for Save Dialog 
    waitForSaveDialog();
    break; 

  case load:
    // wait for Load Dialog 
    waitForLoadDialog();
    break;

  default:
    //Error 
    println("Fail");
    exit();
    break; 
    //
  }//switch
}//func

// ------------------------------------------------

void drawForStateNormal() {

  background(245);
  {
    strokeWeight(2);   
    stroke(#FF0B03);
    fill(0);
    rect(width-380,height-490,360,90,20);// retangolo diff. press.
    fill(255);
   textSize(28); 
   text("Diff.Press.",width-270,height-405);     //diff.press
   textSize(40);
   text(( myKnob2.getValue()- myKnob3.getValue()),width-270,height-445);     //diff.press
  }
  {
  fill(0);
  strokeWeight(2);   
  stroke(#FF0B03);

  rect(width-380,height-390,360,190,20);// retangolo press
  rect(width-380,height-195,360,190,20);// rettangolo massa Temp
   }
  textSize(14);
  showData();

  // title 
  fill(255, 2, 2);
  text("My little Graph program\n\nUse buttons below\n"    //testo e posizione testo
    +"Use Backspace to delete last data point", 
    width-223, 20, 100, 422);

  // ----------------------
  // buttons
  showButtons();
  //
} //draw

// --------------------------------------------------
// functions to show buttons funzione per mostrare i bottoni

void showButtons() {
  //
   strokeWeight(2);   
  stroke(0);
  textSize(15);
  fill(0);
  if ( overSave() ) {
    fill(#FF0303);
  }


  rect(width-50, height-740, 40, 20,5);// modificato posizione bottone "salve"
  fill(255); 
  text("Salve", 
    width-50+2,height-740+9+6);
  // ---
  fill(0);
  if ( overLoad() ) {
    fill(#49C3FA);
  }


    rect(width-50, height-710, 40, 20,5);// modificato posizione" load"
  fill(255); 
  text("Load", 
    width-50+2, height-710+9+6);

  // ---
  fill(0);
  if ( overNew() ) {
    fill(#1FFF03);
  }


   rect(width-50, height-680, 40, 20,5);// modificato posizione "new"
  fill(255); 
  text("New", 
    width-50+4, height-680+9+6);
}

//----------------------------------------------------------------------------
// functions to register if mouse is over buttons funzione da registrare se il mouse è sui pulsanti

boolean overSave() {            // modificato
  return( mouseX > width-50 && 
          mouseY > height-740  && 
          mouseY < height-740+25) ;
}

    boolean overLoad() {                 //modificato
  return( mouseX > width-50 && 
          mouseY > height-710  && 
          mouseY < height-710+25 );
}

boolean overNew() {                         //modificato
  return( mouseX > width -50 && 
          mouseY > height-680  && 
          mouseY < height-680+25 );
}

// ---------------------------------------------------------------------------
// Inputs 

void keyPressed() {

  if (state!=normal)
    return;

  // for the editor: 
  if ( keyCode == DELETE || keyCode == BACKSPACE ) {
    //
    if (points.size()>0)
      points.remove(points.size()-1);
  } else {
    if ( key != CODED ) {
      //
    }
  }
}

void mousePressed() {

  if (state!=normal)
    return;

  // for the buttons 
  if ( overSave() ) {
    initSave();
  }
  //---
  else if ( overLoad() ) {
    initLoad();
  }
  //---
  else if ( overNew() ) {
    points.clear();            //cancellare punti con new
   //  not necessary:
    for (int i = 0; i < 13; i++) { 
      points.add(new PVector(i, 20 + 10*noise(i*0.1)));
    }//for
  }
  //---
  else {
   // points.add(new PVector(points.size(), mouseY/10));
    points.add(new PVector(points.size(), myKnob1.getValue()));
  }
}//func

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath="";
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-"
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2);
  // prepare fileDescription which occurs in the dialogue
  // prepara la descrizione del file che avviene nel dialogo
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//"
    + dateTimeStamp
    + fileExtension);
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription);
  // set state to wait
  state=save;
}

void initLoad() {
  // init load process 
  // reset
  loadPath="";
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension );
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription);
  // set state to wait
  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");
    // go back 

// println ("La finestra è stata chiusa o l'utente ha premuto annulla.");
    // torna indietro

    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");
    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt();
    // go back 
    state=normal;
  }
}

void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt();
    // go back 
    state=normal;
  }
}

void saveIt() {
  // save

  // make array (to save it)
  String[] strs = new String[points.size()];
  int i=0;
  for (PVector pv : points) {
    strs[i]=str(pv.x)+","+str(pv.y);
    i++;
  }//for

  // check if file extension (fileExtension, e.g. .txt) is there 
  int len = savePath.length(); 
  if (len<4 || !savePath.substring( len-4 ).equals(fileExtension)) {
    // file Extension is not present, we have to add it
    savePath += fileExtension; // add the file Extension
  } 

  // save 
  println("Saved: " + savePath);
  saveStrings( savePath, strs );
}//func

void loadIt() {
  // load
//  points.clear(); 
  String[] strs = loadStrings( loadPath );
  for (String s : strs) {
    String[] thisLine=split(s, ","); 
    points.add(new PVector(float(thisLine[0]), float(thisLine[1])));
  }//for
}

// -------------------------------------------------
void showData() {
  //
  // show data
  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points) {

    fill(0);

    // show data
    text(pv.x, 100, y); 
    text(pv.y, 200, y);

    fill(0, 2, 2); 
    stroke(255, 2, 2);
    if (prev.x!=-1) {
      line(10 + pv.x*30, pv.y*10, 
        prev.x, prev.y);
    }
    noStroke();
    ellipse (10 + pv.x*30, pv.y*10, 4, 4);
    prev = new PVector(10 + pv.x*30, pv.y*10); 

    y+=20; //next line
  }//for

  // middle line 
  line( 190, 30, 190, 440);
  //
}

 void serialEvent(Serial p) { 
 inString = p.readString(); 
 char primo=inString.charAt(0);  // primo carattere
 String cifra=inString.substring(1);  // da secondo carattere in poi
 float val=parseFloat(cifra);          // valore da 0-255 o 0-1023, non sò cosa spedisce arduino


 print("val=");    println(val);

 //   inString = trim(inString);

  //    // converte in int e mappa all'altezza dello schermo: 


 switch(primo) { 
   case ('A'): myKnob1.setValue(val);
     break;
   case ('B'): myKnob2.setValue(val);
     break;
   case ('C'): myKnob3.setValue(val);
     break;
      case ('D'): myKnob3.setValue(val);
     break;
 }
 }

I don't know about Arduino but here you can

• New (3 buttons lower right corner)
• Save: A date time stamp is suggested, but you can enter a name.
• Load: dialog
• Delete points with Backspace (keyboard)
• Add points with mouse

At the beginning and when pressing New some points are added, this is not necessary. Search necessary in the code to change this.

A typical stored data file looks like this (comma separated float values)

0.0,27.690079
1.0,27.670195
2.0,27.499521
3.0,27.464329
4.0,27.39308
5.0,27.199102
6.0,26.98093
7.0,26.941555
8.0,26.824514
9.0,26.906185
10.0,26.86552
11.0,26.424377
12.0,26.095716

Chrisir ;-)

//  
// from https : // forum.processing.org/two/discussion/comment/112902/#Comment_112902

// editor path and file extension
final String pathFolder="";
final String fileExtension = ".txt";

// graph content 
ArrayList<PVector> points = new ArrayList();

// states of the program:
// unique numbers for constants: 
final int normal = 0;
final int save   = 1;
final int load   = 2;
///current state (must be one of them) 
int state=normal;

// Paths 
String savePath=""; 
String loadPath=""; 

// ------------------------------------------------
// Core functions of processing 

void setup() {
  size(900, 900);

  // not necessary
  for (int i = 0; i < 3; i++) { 
    points.add(new PVector(i, 20 + 10*noise(i*0.1)));
  }//for
}//func 

void draw() {

  switch (state) {

  case normal:
    drawForStateNormal() ;
    break; 

  case save:
    // wait for Save Dialog 
    waitForSaveDialog();
    break; 

  case load:
    // wait for Load Dialog 
    waitForLoadDialog();
    break;

  default:
    //Error 
    println("Fail");
    exit();
    break; 
    //
  }//switch
}//func

// ------------------------------------------------

void drawForStateNormal() {

  background(0);

  textSize(14);
  showData();

  // title 
  fill(255, 2, 2);
  text("My little Graph program\n\nUse buttons below\n"
    +"Use Backspace to delete last data point", 
    width-123, 20, 100, 422);

  // ----------------------
  // buttons
  showButtons();
  //
} //draw

// --------------------------------------------------
// functions to show buttons

void showButtons() {
  //
  textSize(11);
  fill(128);
  if ( overSave() ) {
    fill(196);
  }
  rect(width-40, height-20, 40, 20);
  fill(255); 
  text("Save", 
    width-40+7, height-9+5);

  // ---
  fill(128);
  if ( overLoad() ) {
    fill(196);
  }
  rect(width-40, height-50, 40, 20);
  fill(255); 
  text("Load", 
    width-40+7, height-50+9+5);

  // ---
  fill(128);
  if ( overNew() ) {
    fill(196);
  }
  rect(width-40, height-80, 40, 20);
  fill(255); 
  text("New", 
    width-40+7, height-80+9+5);
}

//----------------------------------------------------------------------------
// functions to register if mouse is over buttons 

boolean overSave() {
  return( mouseX > width-40 && 
    mouseY > height-20 );
}

boolean overLoad() {
  return( mouseX > width-40 && 
    mouseY > height-50  && 
    mouseY < height-50+25 );
}

boolean overNew() {
  return( mouseX > width-40 && 
    mouseY > height-80  && 
    mouseY < height-80+25 );
}

// ---------------------------------------------------------------------------
// Inputs 

void keyPressed() {

  if (state!=normal)
    return;

  // for the editor: 
  if ( keyCode == DELETE || keyCode == BACKSPACE ) {
    //
    if (points.size()>0)
      points.remove(points.size()-1);
  } else {
    if ( key != CODED ) {
      //
    }
  }
}

void mousePressed() {

  if (state!=normal)
    return;

  // for the buttons 
  if ( overSave() ) {
    initSave();
  }
  //---
  else if ( overLoad() ) {
    initLoad();
  }
  //---
  else if ( overNew() ) {
    points.clear(); 
    // not necessary:
    for (int i = 0; i < 13; i++) { 
      points.add(new PVector(i, 20 + 10*noise(i*0.1)));
    }//for
  }
  //---
  else {
    points.add(new PVector(points.size(), mouseY/10));
  }
}//func

// -------------------------------------------------
// Save and load 

void initSave() {
  // init save process 
  // reset
  savePath="";
  // make date time stamp (the expression nf(n,2) means leading zero: 2 becomes 02)
  String dateTimeStamp = year() 
    + nf(month(), 2) 
    + nf(day(), 2) 
    + "-" 
    + nf(hour(), 2)
    + nf(minute(), 2)
    + nf(second(), 2);
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()
    + "//"
    + pathFolder 
    + "//" 
    + dateTimeStamp
    + fileExtension);
  // open the dialog  
  selectOutput("Select a file to write to", "fileSelectedSave", fileDescription);
  // set state to wait
  state=save;
}

void initLoad() {
  // init load process 
  // reset
  loadPath="";
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension );
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription);
  // set state to wait
  state=load;
}

void fileSelectedSave(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");
    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    savePath=selection.getAbsolutePath();
  }
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");
    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForSaveDialog() { 
  if (!savePath.equals("")) {
    // waiting is over
    saveIt();
    // go back 
    state=normal;
  }
}

void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt();
    // go back 
    state=normal;
  }
}

void saveIt() {
  // save

  // make array (to save it)
  String[] strs = new String[points.size()];
  int i=0;
  for (PVector pv : points) {
    strs[i]=str(pv.x)+","+str(pv.y);
    i++;
  }//for

  // check if file extension (fileExtension, e.g. .txt) is there 
  int len = savePath.length(); 
  if (len<4 || !savePath.substring( len-4 ).equals(fileExtension)) {
    // file Extension is not present, we have to add it
    savePath += fileExtension; // add the file Extension
  } 

  // save 
  println("Saved: " + savePath);
  saveStrings( savePath, strs );
}//func

void loadIt() {
  // load
  points.clear(); 
  String[] strs = loadStrings( loadPath );
  for (String s : strs) {
    String[] thisLine=split(s, ","); 
    points.add(new PVector(float(thisLine[0]), float(thisLine[1])));
  }//for
}

// -------------------------------------------------
// Misc

void showData() {
  //
  // show data
  PVector prev = new PVector(-1, -1); 
  int y=50; 
  for (PVector pv : points) {

    fill(255);

    // show data
    text(pv.x, 100, y); 
    text(pv.y, 200, y);

    fill(255, 2, 2); 
    stroke(255, 2, 2);
    if (prev.x!=-1) {
      line(10 + pv.x*30, pv.y*10, 
        prev.x, prev.y);
    }
    noStroke();
    ellipse (10 + pv.x*30, pv.y*10, 4, 4);
    prev = new PVector(10 + pv.x*30, pv.y*10); 

    y+=20; //next line
  }//for

  // middle line 
  line( 190, 30, 190, 440);
  //
}

// --------------------------------------------------

void setup() { selectInput("Select a file to process:", "fileSelected");

size(img.width, img.height);

}

void draw() {

}

void fileSelected(File file) { if (file == null) { println("Window was closed or the user hit cancel."); } else { println("User selected " + file.getAbsolutePath()); img = loadImage(file.getPath()); // Load the image into the program

} }

Can i get an alternate to select input, i have to specify the path in the location itself anf call back it.

I had a look at that thread you shared, GoToLoop and thanks!! It works great.

As I expected, the problem was in my while loop -- I thought it was what I thought was null, but I think it was more to do with the flag variable and checking the null... whatever...

At anyrate, if anybody's interested, here's the working code as I got it. Now all I have to do is figure out how to hide the code window completely:)

String[] protocol;
String[] fname;

void setup() {
  selectInput("Select a file to process:", "fileSelected");
  // selectInput("Please select canvas picture:", "selectImage");
  while (protocol == null)  delay(100);
  printArray(protocol); 
}

void fileSelected(File selection) {
  if (selection == null) {
    println("Window was closed or the user hit cancel.");
  } else {
    //println("User selected " + selection.getAbsolutePath());
    protocol=loadStrings(selection.getAbsolutePath());
    //printArray(protocol);
  }
}

Hello all. I'm new to this, but not so new to basic coding, but it has been a long time since I've done any serious coding...

Here's my issue -- I have a Processing script that loads in a text file, parses it out and sends some info to an Arduino board. It works great, but I'd like to present the operator with the option of selecting a file, but I'm having trouble getting my head around the concept of "callback" stuff and in specific how to use it with the selectInput() function.

For the purposes of this, I have stripped out all the other stuff and just have the file load bits...

String[] protocol;
String[] fname;
int flag=0;

void setup() {
  selectInput("Select a file to process:", "fileSelected");
  while(flag==0){
    if(protocol!=null){
      flag=1;
    }
  }
  println(protocol[0]);  
}

void fileSelected(File selection) {
  if (selection == null) {
    println("Window was closed or the user hit cancel.");
  } else {
    println("User selected " + selection.getAbsolutePath());
    protocol = loadStrings(selection.getAbsolutePath());
  }
}

My idea is that by putting the while loop it should hold the code until the variable protocol has something other than null. I have a feeling that I'm barking up the wrong tree with this and that null is the wrong thing to be checking for?

Any ideas or links to some tutorials or whatever would be greatly appreciated!!

Greg

here is an example to demonstrate the states.

This full sketch just displays the content of a text or mtl file after you loaded it.

I hope this helps.

Chrisir ;-)

// editor path and file extension
final String pathFolder="texts";
final String fileExtension = ".mtl";

// states of the program:
// unique constants: 
final int normal = 0;
final int load   = 1;
///current state (must be one of them) 
int state=normal;

// Path 
String loadPath=""; 

String str="nothing loaded\nuse button in the lower right corner ";

// ------------------------------------------------
// Core functions of processing 

void setup() {
  size(900, 900);
} // func 

void draw() {

  switch (state) {

  case normal:
    drawForStateNormal() ;
    break; 

  case load:
    // wait for Load Dialog 
    waitForLoadDialog();
    break;

  default:
    //Error 
    println("Fail");
    exit();
    break; 
    //
  } // switch
} // func

// ------------------------------------------------

void drawForStateNormal() {

  background(0);

  textSize(14);

  // title 
  fill(255, 2, 2);
  text("Demo for selectInput", 
    width-123, 20, 100, 422);

  // show the text the user loaded 
  fill(255);
  text(str, 
    20, 20, width-170, height-20);

  // ----------------------
  // button
  fill(128);
  if ( overLoad() ) {
    fill(196);
  }
  rect(width-40, height-50, 40, 20);
  fill(255); 
  text("Load", 
    width-40+5, height-50+9+5);
  //
}//func

//----------------------------------------------------------------------------
// functions to register if mouse is over buttons 

boolean overSave() {
  return( mouseX > width-40 && 
    mouseY > height-20 );
}

boolean overLoad() {
  return( mouseX > width-40 && 
    mouseY > height-50  && 
    mouseY < height-50+25 );
}

boolean overNew() {
  return( mouseX > width-40 && 
    mouseY > height-80  && 
    mouseY < height-80+25 );
}

// ---------------------------------------------------------------------------
// Inputs 

void keyPressed() {

  if (state!=normal)
    return;
}

void mousePressed() {

  if (state!=normal)
    return;

  // for the buttons 
  if ( overLoad() ) {
    initLoad();
  }
  //
}//func

// -------------------------------------------------
// load functions 

void initLoad() {
  // init load process 
  // reset
  loadPath="";
  // prepare fileDescription which occurs in the dialogue
  File fileDescription = new File( sketchPath()+"//"+pathFolder+"//"+"*" + fileExtension );
  // open the dialog
  selectInput("Select a file to load", "fileSelectedLoad", fileDescription);
  // set state to wait
  state=load;
}

void fileSelectedLoad(File selection) {
  // the 'callback' function
  if (selection == null) {
    // println("Window was closed or the user hit cancel.");
    // go back 
    state=normal;
  } else {
    // println("User selected " + selection.getAbsolutePath());
    loadPath=selection.getAbsolutePath();
  }
}

void waitForLoadDialog() { 
  if (!loadPath.equals("")) {
    // waiting is over
    loadIt();
    // go back 
    state=normal;
  }
}

void loadIt() {
  // load
  String[] strs = loadStrings( loadPath );
  str = join(strs, "\n");
}
//

No problem.

Look at selectInput

Inside the call back function, copy the file path inside a global String variable loadPath that you declared before setup ().

Then use loadStrings together with loadPath to open the mtl.

I always use a state system to make sure I only load once loadPath is set. So once the load command gets in I tell draw() to be in a state waitForLoad (integer variable / constant) and I then start selectInput. Once loadPath is set, I load and set the state back to stateNormal (integer variable as well).

For example:

1. The application downloads allsamples.xml or .csv from a known source. It contains a list of sample names and URLs, like "wobble" and "http://mysampleserver.com/wobble.wav"
2. For each entry in allsamples, it creates a file in a sketch folder "/data/samples/": saw.sample, wobble.sample, etc.
3. These are just text files that each contain one URL string.
4. When the user pushes a button, launch selectInput pointed at that directory. You are having them use the file browser to pick a remote file URL for download from a provided list.

Yes you are right. What I would like is to be able to let the user browse through the files that can be found in this web directory and the file that he or she chooses will be somehow buffered and loaded into the sketch so it can then be triggered in the sampler. I will use the Minim library for the buffering I think. But it would be really nice if the browsing of the web directory could be solved first. I guess it will be kind of like selectInput or selectFolder but instead of selecting from hard drive we want to select from web directory. At the moment I have only uploaded the .wav files on a localhost until I have figured everything out and this will first of all just be a proof of concept for my school project so I only need to show that I have figured out how to make it work.

I haven't seen this kind of browsing perse before so my idea is just being based off of a product that I want to make happen. For starters a workaround will be more than welcome for now.