Signal connectors without QApplication or QCoreApplication

Question

I would like to encode a DLL that must be loaded by a non-QT application. As a result, when my DLL is loaded, I do not have QApplication/QCoreApplication . As a result, my Signal / Slot mechanism does not work.

I searched deeply in the Qt forums, but could not get a good answer on how to deal with such a problem. I created QThread , moved my QObjects to this thread, and created a fake QApplicationCore and called it the exec() function inside the QThread run() function. Thus, my signal slot mechanism worked, but I am not happy with this indirect solution. I should be able to activate my thread slots from the main thread execution space other than Qt. What is the correct way to work with such dll plugins? Direct answers and recommendations on reading the source are welcome. thank you

Note. The external application loading my DLL is a Windows application. This is a third-party application, and I can’t touch it.

Answer 1

Qt signals and slots require an event loop to start. You must start the event loop in the stream that exist in your QObject. Of course, you cannot run it in the main thread of your application (since it does not use Qt), therefore, starting QThread , moving your QObject objects to this stream (or creating these objects in the run() method) and running exec() in the run() thread is the right solution.