Logical steps to make this happen?

Programming Questions

roowillia..

Logical steps to make this happen?

in Programming Questions • 1 month ago

Hello,

I am in the process of learning Processing through setting myself little projects. I am picking up the syntax, but I am having trouble with thinking of the structure of programs...

I am using Twitter4j and a streaming code snippet available over here: https://github.com/neufuture/SimpleTwitterStream

I have a listener that looks like this:

StatusListener listener = new StatusListener() {
public void onStatus(Status status) {
println("@" + status.getUser().getScreenName() + " - " + status.getText());
}

If I wanted to cause that to draw a rectangle, wait a little, then draw a text(tweet) for 5 seconds, and then once the tweet has disappeared, hide the rectangle , what would be the steps needed to make that happen?

I don't want anyone to write code for me, but rather explain how I'd need to do it, eg.

1. Put status.getUser().getScreenName() and status.getText() into global String variables

2. Write a displayTweets() function....

3. Etc.

Looking forward to hearing from anyone!

Cheers

- Roo

Replies(3)

PhiLho

Re: Logical steps to make this happen?

1 month ago

Lazy but fast answer:
Go to the Technical FAQ, look at the entries, particularly the Sequencing and timing section.
I believe / hope it can help you in understanding the logic behind animations in Processing (otherwise, any remark is useful to improve the articles...)

GoToLoop

Re: Logical steps to make this happen?

1 month ago

I don't think a listener should be tasked to do all of the processes involved in a triggered event.
It should only register the occurrence and return. The other parts of the program gonna take care of it.

For the data related to the event, it has to be recorded in a structure.
For a twitter, I guess a Queue (FIFO) one is more appropriate.

http://docs.oracle.com/javase/7/docs/api/java/util/Queue.html

GoToLoop

Re: Logical steps to make this happen?

1 month ago

Some Queue examples I've found here w/ me. Just to give ya an idea how it works:

/**
 * Chase-Shadow Circles
 * ArrayDeque Edition
 *
 * http://forum.processing.org/topic/newbie-question-understandig-problems-with-arrays
 * http://www.creativecoding.org/lesson/basics/processing/arrays
 */

import java.util.*;

final static short maxCircles = 0100;
final static Queue<Circle> circles = new ArrayDeque(maxCircles);

boolean isFull;
short numCircles, sz;

void setup() {
  size(1000, 400);
  frameRate(100);
  smooth();

  noStroke();
  fill(0100<<030);

  mouseX = width>>1;
  mouseY = height>>1;
}

void draw() {
  background (-1);

  addCircle();

  sz = 0;
  for (Circle c: circles)  c.display();
}

void addCircle() {
  if (isFull)                            circles.remove();
  else if (++numCircles == maxCircles)   isFull = true;

  circles.add( new Circle() );
}

class Circle {
  final short x, y;

  Circle() {
    x = (short) mouseX;
    y = (short) mouseY;
  }

  void display() {
    ellipse(x, y, sz, sz++);
  }
}

/**
 * Trailing Deque (v3.41)
 * by  quarks (2013/Feb)
 * for rialobran
 * mod GoToLoop
 *
 * http://forum.processing.org/topic/drawing-a-trail-for-a-moving-object
 */

import java.util.Queue;
import java.util.ArrayDeque;

final static byte MAX_TRAIL_POINTS = 5;
final static Queue<PointXY> trails = new ArrayDeque(MAX_TRAIL_POINTS);

PointXY tt;

byte currTrailSize;
boolean isFull, trailOrLinked;

final static color BG = 0350, FG = #0000FF;
final static short FPS = 30, BOLD = 3;

final static String GFX = JAVA2D; // use JAVA2D or P2D

void setup() {
  size(800, 600, GFX);
  frameRate(FPS);
  smooth();

  keyPressed();

  stroke(FG);
  strokeWeight(BOLD);
}

void keyPressed() {
  if (trailOrLinked = !trailOrLinked)    noLoop();
  else                                   loop();
}

void mousePressed() {
  redraw();

  if (isFull) {
    tt = trails.remove();
    trails.add( new PointXY(mouseX, mouseY) );
    return;
  }

  trails.add( new PointXY(mouseX, mouseY) );
  tt = trails.element();

  if (++currTrailSize == MAX_TRAIL_POINTS)   isFull = true;
}

void draw() {
  background(BG);
  for (PointXY t: trails)    tt = t.action(tt);
}

final class PointXY {
  final int x, y;

  PointXY(int px, int py) {
    x = px;
    y = py;
  }

  PointXY action(PointXY other) {
    line(other.x, other.y, x, y);
    return this;
  }
}

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