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Index › Programming Questions & Help › Syntax Questions › Call a function before applet exit
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Call a function before applet exit (Read 688 times)
brik
Call a function before applet exit
Apr 2nd, 2009, 5:16am  
Hi there, i'd like to make a function that is called when the user navigates away from the applet window on my website. Is this possible? Is navigating away the same as closing the window of a non-web-based applet? If so, could I use java.awt.event.WindowAdapter and windowListeners?
Thanks,
Rob
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PhiLho 
Re: Call a function before applet exit
Reply #1 - Apr 2nd, 2009, 11:43am  
In a MySQL sketch, I use this code to close the connection:
Code:
void stop()
{
  println("Stopping connection");
  mysql.close();
}

The stop() method is called when the sketch closes. Although I am not sure it is properly called when it is an applet embedded in a browser. And it is hard to verify, except by sending a signal to a server perhaps.
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JohnG
Re: Call a function before applet exit
Reply #2 - Apr 3rd, 2009, 4:00am  
You should probably add in super.stop(); at the end of that function so Processing's stop code still gets called.
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PhiLho 
Re: Call a function before applet exit
Reply #3 - Apr 3rd, 2009, 4:42am  
Excellent advice, JohnG!
I checked PApplet code, and indeed it does some clean-up stuff (like g.dispose()).
I also saw the comment:
  * Called by the browser or applet viewer to inform
  * this applet that it should stop its execution.
  * <p/>
  * Unfortunately, there are no guarantees from the Java spec
  * when or if stop() will be called (i.e. on browser quit,
  * or when moving between web pages), and it's not always called.
which confirms there is no guarantee of call on browser/page/tab closing/moving away.
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