How to make the main GUI thread 'wait' until a separate pop-up window is disappeared?

Don't use a separate JFrame for this is what modal dialogs were built for. Use either a JOptionPane or a modal JDialog.

I have an object which is invoked from the main GUI thread and shows a separate JFrame If you want to show more than one TopLayoutContainer(s) maybe it is better to look for JDialog because with that you can play with ModalityType & toFront(). Isn't method show() deprecated and replaced with method JDialog. SetVisible(boolean)?

3 +1 but please take care of your grammar and spelling. – asgs May 20 at 21:59 @Andrew Thompson again thanks, – mKorbel May 20 at 22:35.

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