SWT Based GUI getting black on maximizing from minimizing staus in Full Size

Question

I've a GUI based on Eclipse SWT/RCP . When that GUI is in Full Size and I minimize it and then maximize it , I see a dark/black over the Ui for a second or more and then it becomes normal. I want to know, what might be the reason for same

Following is the screenshot -

Answer 1

This usually indicates that you have a code that runs longer than it should on an event listener and the paint events are not dispatched until that code is done. Hence you see the black areas until they are dispatched and painted. I recommend checking the logic on listeners especially for resize and focus events if you have any.