Touch Events are often lost (using QtWinMigrate)
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We are porting a windows MFC application to Qt/QML using the QtWinMigrate module. Unfortunately, often Touch events are lost, for example we have to press a button several times ( typically 8 times, sometimes 30 times) until it reacts to touch. We rely on the Windows behaviour to translate touch events to "normal" mouse events.
Even the window title area for dragging does not work with Touch.We are looking for hints how to solve this. Without QtWinMigrate, everything works fine so far concerning Touch. Even with QtWinMigrate, Touch still works also for MFC buttons in simple test applications. But as soon as we set a breakpoint for example in QWindowsContext::windowsProc(...), touch stops working.
Maybe there is a time/delay test on touch and mouse events in order to consolidate them somewhere in Qt/QML?
This could explain why sometimes touch events come through and sometimes not.(BTW we checked with Qt 5.2.1, 5.3.0 and 5.3.1.. QQuickView based QML scenes suffer also from missing most touch events, whereas QQuickWidget is the only way to get all Touch events in our scenario - unfortunately we need more time to port the whole app to Qt so this is no option at this time).