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Has anyone experienced phantom touch inputs with QML on Android?

  • Hi everyone,

    My application was originally GraphicsView based and when run on Android that behaved just fine, albeit poor performance due to the lack of OpenGL rendering.

    Now everything was drawing through the QPainter class so rewriting it to use the QML Scene Graph wasn't a big job and was done by using a QQuickPaintedItem QML item. Performance was great, everything rendered fine, no problems there.

    But after a few minutes (and it appears random when it starts doing it) I'm seeing incorrect touch events being introduced on the device.

    This is on a Nexus 7, and it's not an issue with the application as I turned on the pointer display options under the device's Developer Mode menu and these fake presses are showing up on the OS as touch events.

    -I've never seen this before so seems to be Qt specific, not an issue with the device.
    -It happens whether or not the OpenGL rendering is enabled via the QML item's render target (QQuickPaintedItem::FramebufferObject).
    -The application is a game, it's not introducing touch events as part of its programming.
    -The touch events can trigger the soft keys such as the back button or application minimisation.
    -I couldn't reproduce it when running under the GraphicsView framework, instead of QML.

    Has anyone seen anything like this? I may be able to re-produce it on camera later in the week if that helps.

  • Sorry I forgot to mention this is on 5.2 RC1

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