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QApplication focusChanged

  • Hi all,

    I'm trying to create a Qt5.3.2 GUI program on Rpi3 and I need focusChanged signal from qApp.
    I've got a problem with the touchscreen.
    If I connect a mouse everything is fine and I received focusChanged signals on my slot functions, but if I use touchscreen only this signal not emitted.

    Can somebody help me?
    Thank you in advance.

  • Moderators

    First I'll admit that I've never used RPi with a touchscreen, so I can't help much.

    But I suggest trying out newer Qt version (5.9.4 or 5.10.1), maybe that issue was fixed. Also, make sure you have all input handling libraries installed.

  • @sierdzio Thanks, I'll try a newer qt version!

  • I installed 5.7.1 (it is the newest version for RPi), but the issue is same.

    Some observations:

    • QTouchDevices found 1 device (Capabilities: Position | NormalizedPosition; Type: TouchScreen)
    • The cursor follow my touch,
    • If I tap into the QLineEdit -> focusChanged signal (from qApp) NOT emitted; cursor NOT blinking in the field
    • If I tap on the QPushButton -> QPushButton clicked signal is emitted

    Do you have any idea?

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