[BUG] Some few exception that could be avoided


Hi Jules,

I’ve enabled stopping in all exception while debugging.
Sometime, when I start a juce code, I get an exception which is not handled correctly (only in enterMainApplicationLoop => exit). I think this is an error in general Juce code. This occurs when ImageButton is used Here is what’s happening, and how to avoid it:


  • WinMain is called (or whatever entry point)
  • enterMainApplicationLoop is called
  • runDispatchLoop is called, and then dispatchMessage
  • juce_wndProc is then called with a WM_MOVE message (no WM_PAINT message has been processed yet)
  • doMouseMove is called
  • handleMouseEnter is then called because the current captured HWND is not ours (which doesn’t exists yet)
  • Then the code tries to find what component is at the cursor position
  • The hitTest method of ImageButton is called, but because ImageButton:: paintButtion is called yet, the imageW and imageH members are still not defined (they are 0). hitTest then tries to divide by imageW and imageH which causes a divide by zero exception.

To avoid this, I think the correct behaviour would have been to change in the setImages method (line 108 of juce_ImageButton.cpp):

    if (resizeButtonNowToFitThisImage && normalImage != 0)
        setSize (normalImage->getWidth(),


    if (resizeButtonNowToFitThisImage && normalImage != 0)
        setSize (normalImage->getWidth(),
        imageW = normalImage->getWidth(); imageH = normalImage->getHeight();

Maybe imageX and imageY should be changed too.

Please confirm, and/or take notice for next update.




Thanks for that Cyril, well spotted. I’ll fix it for the next release.