How can I wait for a user event from inside a function?

Programming Questions

jas0501

How can I wait for a user event from inside a function?

in Programming Questions • 1 year ago

My goal:

Insert lines

breakAtLine("function",linenum);

with controlled stepping through the code.

Given the code below, where and/or how can I set waiting = false;

I tried keyPressed() and mouseClicked() but they don't seem to be called. I assume they are called once per frame.

boolean waiting;

public void breakAtLine(String name,int linenumber)

{

waiting = true;

println("In "+name+" at line:"+linenumber);

while(waiting)

{

}

Replies(3)

dr.mo

Re: How can I wait for a user event from inside a function?

1 year ago

i assume that keyPressed() and mouseClicked() are handled in between calls to draw() - so if you break inside draw those functions do not get evaluated and so you can not handle a keypress that way and hence you have no way of changing your variable 'waiting'. my suggestion would be to see if you can handle keypresses directly use java.awt.event.KeyListener or something

Manindra29

Re: How can I wait for a user event from inside a function?

1 year ago

I think you're looking for something like this:

import javax.swing.JFrame;
public void setup() {
size(200, 200);
smooth();
ChildPApplet child = new ChildPApplet();
child.init();
JFrame childFrame = new JFrame();
childFrame.setBounds(100, 100, 410, 410);
childFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
childFrame.add(child);
childFrame.setVisible(true);
}
boolean waiting = false;
public void draw() {
background(252);
fill(0);
text("Parent PApplet\n\nClick Me!", 30, 30);
}
public void mouseClicked() {
waiting = !waiting;
}
public class ChildPApplet extends PApplet implements Runnable {
public void setup() {
size(400, 400);
noStroke();
smooth();
}
int c = 0;
public void draw() {
background(252);
fill(50, random(250), random(250));
ellipse(random(width / 3, width/2), random(height / 3, height/2), 40, 40);
if (waiting)
System.out.println("First ellipse drawn");
while (waiting) {
if (c++==0)break;
try {
Thread.sleep(10);
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
fill(50, random(250), random(250));
ellipse(width / 2, height / 2, 50, 20);
if (!waiting)
System.out.println("Second ellipse drawn");
while (!waiting) {
if (c++==1)break;
try {
Thread.sleep(10);
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}

The screen seems to get refreshed after draw() is called.

jas0501

Re: How can I wait for a user event from inside a function?

1 year ago

That will do the trick just fine.

Thanks.

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