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Qt not registering click event on RPI

  • Hello all,

    I have an issue with my program for RPI where on some forms, the touchscreen works correctly. On others, it does not. The mouse works perfectly fine. I am not sure where to start debugging this? Has anyone else ran into this issue? Please let me know


  • I've seen touch drivers fail to deliver release events, or the Qt platform input plugin fail to recognize them. If something like a button has grabbed the touch and is waiting for it to end before releasing it, the rest of the UI may fail to respond.

    https://bugreports.qt.io/browse/QTBUG-68451 may be relevant

    My first step would be to turn on all logging and see if there is an asymmetry in touch begin versus end events. Setting the environment variable QT_LOGGING_RULES to \*.\*=true will give you lots of output. Individual categories can then be turned off by appending category.subcategory=false, separated by ;.

    Installing an event filter or native event filter on the QCoreApplication can be helpful.

    If this is a multitouch interface, it may be a version of https://bugreports.qt.io/browse/QTBUG-63779.

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