Is there a way to override the windowClosing function?

I did say no originally but I have managed to find a work arround


The solution to this particular problem (without changing the library code) would be to create a class that extends GWindow and in that class create an inner class that extends java.event.WindowAdapter. This inner class would then be modified to call a method immediately before the window is closed.

So in your sketch create a new tab called GWindowPlus.java note the extension because this will NOT be an inner class and making it a seperate class is better than  the alternative - a static inner class. In this tab copy and paste the following code.

GWindowPlus.java

1. import g4p_controls.*;
2. import processing.core.*;
3. import java.awt.event.WindowAdapter;
4. import java.awt.event.WindowEvent;
5. import java.lang.reflect.Method;
6. 
   
7. public class GWindowPlus extends GWindow {
8. 
   
9.   public Method callback = null;
10.   public Object callbackObj = null;
11. 
    
12.   public GWindowPlus(PApplet theApplet, String name, int x, int y, int w, int h, boolean noFrame, String mode) {
13.     super(theApplet, name, x, y, w, h, noFrame, mode);
14.     removeWindowListener(winAdapt);
15.     setActionOnClose(CLOSE_WINDOW);
16.   }
17. 
    
18.   public GWindowPlus(PApplet theApplet, String name, int x, int y, PImage image, boolean noFrame, String mode) {
19.     super(theApplet, name, x, y, image, noFrame, mode);
20.     removeWindowListener(winAdapt);
21.     setActionOnClose(CLOSE_WINDOW);
22.   }
23. 
    
24.   public void setCloseCallMethod(Object obj, String methodName) {
25.     try {
26.       callback = obj.getClass().getMethod(methodName, new Class<?>[] { GWindow.class } );
27.       callbackObj = obj;
28.     }
29.     catch (Exception e) {
30.       PApplet.println("Unable to find method" +  methodName);
31.     }
32.   }
33. 
    
34.   public void setActionOnClose(int action) {
35.     switch(action) {
36.       case KEEP_OPEN:
37.       removeWindowListener(winAdapt);
38.       winAdapt = null;
39.       actionOnClose = action;
40.       break;
41.     case CLOSE_WINDOW:
42.     case EXIT_APP:
43.       if (winAdapt == null) {
44.         winAdapt = new GWindowAdapterPlus(this);
45.         addWindowListener(winAdapt);
46.       } // end if
47.       actionOnClose = action;
48.       break;
49.     } // end switch
50.   }
51.  
52. 
    
53.   public class GWindowAdapterPlus extends WindowAdapter {
54.     GWindow window;
55. 
    
56.     public GWindowAdapterPlus(GWindow window) {
57.       this.window = window;
58.     }
59. 
    
60.     public void windowClosing(WindowEvent evt) {
61.       switch(actionOnClose) {
62.       case CLOSE_WINDOW:
63.         window.papplet.noLoop();
64.         if (callback != null) {
65.           try {
66.             callback.invoke(callbackObj, window);
67.           }
68.           catch (Exception e) {
69.             PApplet.println("ooops \n" + e.getStackTrace());
70.           }
71.         }
72.         G4P.windowCloser.addWindow(window);
73.         break;
74.       case EXIT_APP:
75.         System.exit(0);
76.         break;
77.       }
78.     }
79.   }
80. }

An example sketch to demonstrate the new class.

Main tab

1. import g4p_controls.*;
2. GWindowPlus wp;
3. 
   
4. public void setup(){
5.   size(480, 320);
6.   wp = new GWindowPlus(this, "My window", 0, 0, 240, 120, false, JAVA2D);
7.   wp.addDrawHandler(this, "win_draw1");
8.   // Define the method tyo call on closing the winodw
9.   wp.setCloseCallMethod(this, "windowClose");
10. }
11. 
    
12. public void draw(){
13.   background(230);
14.  
15. }
16. 
    
17. // This method will be executed immediately before
18. // the window closes
19. public void windowClose(GWindow window){
20.   println("Window closed");
21. }
22. 
    
23. synchronized public void win_draw1(GWinApplet appc, GWinData data) {
24.   appc.background(230);
25. }