Preventing a PApplet closing the calling Java program

adamgreen

Ok, so I have this Java Program developed primarily in Swing (Enthusiasm yay!). A small part of it uses Unfolding, a processing library for create maps (like geographical maps). Anyway, all of this is built in a class called MapProcessingApplet an extension of PApplet.

Now to open this window from the calling window I implement and actionlistener on a button, await the click and then do the following:

MapProcessingApplet mapApplet = new MapProcessingApplet();
PApplet.runSketch(new String[]{"<Package>.MapProcessingApplet"}, mapApplet);

(Where the is actually configured correctly).

Now, this runs fine, the window opens, it shows a rather lovely map (thank you, unfolding), but when I click the close button (the cross in the top right) it doesn't just close the PApplet window, it also closes the window from which I call it and terminates the entire program.

Is there a way to prevent it from doing this?

(You know, because kamikaze maps are cool and all, but not really what the end user is looking for in a program)

GoToLoop

https://forum.Processing.org/two/discussion/12319/using-papplet-runsketch-to-create-multiple-windows-in-a-ps3-sketch#Item_25

adamgreen

Thank you, except I think I'm using processing 2 not processing 3, I am assuming I remove window listeners from the frame rather than the surface right?

quark

Yes remove them from the frame.

GoToLoop

Variable frame in both P2 & P1 is already a JFrame.
I guess it's very easy to adapt my solution to old Processing versions. :D

http://docs.Oracle.com/javase/8/docs/api/javax/swing/JFrame.html

adamgreen

the frame variable is actual just a Frame although it can be cast to a JFrame. I cast it to JFrame and did:

((JFrame) frame).setDefaultCloseOperation(HIDE_ON_CLOSE);

with no success, also removed the WindowListeners

GoToLoop

The frame variable is actual just a Frame although it can be cast to a JFrame.

Indeed field frame is declared as datatype Frame. However it points to a JFrame object instead. :P

... with no success, ...

My solution relies on class Window's removeWindowListener() method: :-B

http://docs.Oracle.com/javase/8/docs/api/java/awt/Window.html#removeWindowListener-java.awt.event.WindowListener-

static final void removeExitEvent(final PSurface surf) {
  final java.awt.Window win
    = ((processing.awt.PSurfaceAWT.SmoothCanvas) surf.getNative()).getFrame();

  for (final java.awt.event.WindowListener evt : win.getWindowListeners())
    win.removeWindowListener(evt);
}

adamgreen

Ok, but PSurface doesn't seem to be part of the Processing 2 Core library

quark

Did you remove all WindowListeners?

If you have removed them all you can try the DO_NOTHING_ON_CLOSE option and add your own WindowListener/ WindowAdapter to handle the window closing event.

adamgreen

Actually that's probably a more elegant solution, I'll try attaching my own WindowListener event. The DO_NOTHING_ON_CLOSE seems to be having no effect.

adamgreen

Ok, so removing all the WindowListeners and attaching my own to open a new window hasn't worked either. It kills even the newly open window

quark

It is the approach I took in the G4P library and it worked for me. :)

GoToLoop

Ok, but PSurface doesn't seem to be part of the Processing 2 Core library...
Thank you, except I think I'm using Processing 2 not Processing 3, ...

• You've already confirmed you're using P2.
• I have already told you that you need to port my P3 solution to P2.
• And I have already told you that frame already points to a JFrame object.

adamgreen

Ok, well I've attempted to port you solution. I created a loop for removing all the WindowListeners from the JFrame. I ran this program in a Debugging session and did a variable watch on the JFrame in PApplet.

Upon inspection of the WindowListeners within this frame, there were no windowListeners set to the PApplet.

As far as I can tell all windowListeners have been removed from the frame. The default close operation was also set on both "HIDE ON CLOSE" and "DO NOTHING ON CLOSE"