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Riein
11th September 2014, 19:32
Strange problem I encountered working with a Qt program, it looks like the Qt Program will cause some communication freeze between non-Qt windows.
What I mean is if I try to drag a file into my Qt window, regardless of if I have setAcceptDrops and the dragEnter, dragMove, dropEvent methods set everywhere possible, the window or area where the file originated from while trying to cross into my Qt application will freeze. The Qt application will continue to work normally with no problems, but the window that I tried to drag from will be frozen and the mouse will not respond in that area. Similarly, if I am using QApplication::clipboard to copy text from my Qt application and paste into Microsoft Word or Mozilla Firefox or any such program, then the program will freeze but my Qt application will run normally. It is only until I close my Qt app that the other windows will unfreeze and the freezing only occurs to the window that the Qt app directly interacts with.

I suspect that there is some background process/thread that continually loops until the program is closed that does not allow the operation to finish. After closing the Qt program, the process will finish and paste the text or respond to the mouse clicks that I performed in the respective window.

Does anyone have an idea as to something I might need to call in order to end these threads or stop the background from hanging? Using Qt 4.7.4 and have tried running the app on multiple computers with the same result. Any help is much appreciated.