Problem preventing Air applications from exiting1

In case you want to do some action before your application exits you should do the following:

NativeApplication.nativeApplication.addEventListener(Event.EXITING , windowExitingHandler);

And take whatever actions inside the method windowExitingHandler()

This method should have the following form:

    private function windowExitingHandler(event:Event):void
    {
        event.preventDefault();
        ....
        ....
    }

So, you must call, event.preventDefault(), to stop default exiting behaviour and introduce you own, then later you call 

NativeApplication.nativeApplication.exit();

But take care, the exit() method, must be called after the windowExitingHandler() method is called.

An Example of wrong form:

    private function windowExitingHandler(event:Event):void
    {
        event.preventDefault();
        ....
        NativeApplication.nativeApplication.exit(); // WRONG

    }
 

It won't close, and you've to do the following:

    private function windowExitingHandler(event:Event):void
    {
        event.preventDefault();
        ....
        setTimeout(onApplicationExitTimer, 100);
    }
    
    private function onApplicationExitTimer():void
    {
        NativeApplication.nativeApplication.exit();
    }

Note:

I've experienced this on Mac, and not sure whether the same applies to other platforms.