How to display element# of ArrayList as text

Answers

• TfGuy44

  June 2017 edited June 2017

  You want to display some text, so you need to use the text() function.

  The text() function takes some parameters to know what to do.

  The first parameter is the text to display, and should be an expression that evaluates to a String.

  The text you want to display is the position of the Box object. The Box object is storing its position in the PVector pos. You can verify this immediately because the box is being drawn at the position (0,0,0) after a call to translate() is moving the origin to that point. Thus, the numbers you want to display are the x, y, and z components of the PVector pos.

  You can access these components directly, as you have done so in the call to translate(): pos.x, pos.y, and pos.z.

  Since you want an expression that evaluates to a string, start with a blank string: "", and append things to it using the string concatenation operator: +.

  Make sure to put some spaces in between your numbers! These spaces should also be strings!

  text( "" + pos.x + " " + pos.y + " " + pos.z , 0, 0, 0);
• Nicho247

  June 2017

  Hi TfGuy44 -

  Thank you for reading and attempting to help me with my problem. Unfortunately, the coordinates of the box are not what I am interested in. I am interested in what is the position of each element in the Array. Said differently, an array holds many objects, in some sort of order. I am interested in that order. One of these boxes is box #1, box #2, box #3, etc. I want these boxes labeled with 1, 2, 3, etc. I don't need the coordinates of box 1, 2, 3, etc.

  Thanks, Nick
• GoToLoop

  June 2017 edited June 2017

  List::indexOf():
  http://docs.Oracle.com/javase/8/docs/api/java/util/List.html#indexOf-java.lang.Object-
• jeremydouglass

  June 2017 edited June 2017

  @Nicho247 -- the confusion in part is the way you are using the word "position," which you later clarify as "order." Clearer to say that you want the index of each element in the array (or ArrayList, or List, etc.). Using "index" will make it easier for others to understand and help you -- and easier to look up functions yourself. For example, notice in IntList how get, set, and remove all take an "index" as an argument.

  https://processing.org/reference/IntList.html
• Chrisir

  June 2017

  Make int index part of your class, fill it in the constructor with boxes.size()-1

  Show index with text()

  Works as long as you don't delete

  Not tested
• Chrisir

  June 2017

  import peasy.*;
  import peasy.org.apache.commons.math.*;
  import peasy.org.apache.commons.math.geometry.*;
  
  ArrayList<Box> boxes = new ArrayList(); 
  PeasyCam cam ; 
  
  void setup() {
    size(900, 900, P3D);
    cam = new PeasyCam(this, 0, 0, 0, 500);
    boxes=generate();
  }
  
  void draw() {
    background(0); 
    // lights();
    for (int i = 0; i<boxes.size(); i++) {
      //for (int i = 0; i<1; i++) {
      boxes.get(i).show();
    }
  }
  
  // ------------------------------------------------------
  
  ArrayList<Box> generate() {
  
    float r = 67; 
    ArrayList<Box> boxes = new ArrayList<Box>();
    PVector pos=new PVector(); 
  
    for (int x = -1; x < 2; x++) {
      for (int y = -1; y < 2; y++) {
        for (int z = -1; z < 2; z++) {
  
          float newR = r/3;
  
          Box b = new Box(pos.x + x*newR, 
            pos.y + y*newR, 
            pos.z + z*newR, 
            newR, 
            boxes.size());
  
          int sum = abs(x) + abs(y) + abs(z);
  
          if (sum > 1) {
            boxes.add(b);
          }
        }
      }
    }
    return boxes;
  }
  
  // ========================================================
  
  class Box {
  
    PVector pos;
    float r;
    int index; 
  
    Box(float x, float y, float z, 
      float r_, 
      int index_) {
      pos = new PVector(x, y, z);
      r = r_;
      index = index_;     //index = boxes.size();
    }
  
    void show() {
      pushMatrix();
      translate(pos.x, pos.y, pos.z);
  
      pushMatrix(); // store Matrix
      fill(255, 2, 2); //red
      textAlign(CENTER, CENTER); // alignment  
      textMode(SHAPE);           // looks much better 
      text(index, 0, 0, 0); // this is new
      popMatrix(); // restore Matrix
  
      // how to draw the box
      if (keyPressed) {
        noStroke();
        fill(255, 100);
      } else {
        noFill(); 
        stroke(255);
      }
  
      box(r);
  
      popMatrix();
    }
  }//class 
  //
  
• Chrisir

  June 2017

  I think generate() should not be inside the class, since it works on the list of all boxes

  I made a menger sponge now from it, so come back for more help.