void setExampleWidgetBackgroundImage () {
		if (backgroundImageButton != null && backgroundImageButton.isDisposed()) return;
		Control [] controls = getExampleControls ();
		for (int i=0; i<controls.length; i++) {
			controls [i].setBackgroundImage (backgroundImageButton.getSelection () ? instance.images[ControlExample.ciBackground] : null);
		}
	}