Qt5 doesn’t grab keyboard strokes

  • I already posted this message, but perhaps in the wrong sub forum...

    I made a small test app in C++ (no QML). The main widget is a QWidget. It has 1 QLineEdit, 1 QSpinBox and 2 QPushButton. One to quit, the other to show the “About Qt” dialog.

    I can type text and numbers in QLineEdit and QSpinBox as long as I change the focus with the tab key. If I use the mouse to change the focus or if I show the “About Qt” dialog, the characters I type go to the console instead of my Qt app : I can see them when I quit.

    I run the app with the CLI option : -platform eglfs, kernel v3.6, Raspbian Wheezy, RPi model B.

    Any idea ?

  • I have a QML/WebView in Qt5, where I see a similar behavior when I enter text in text boxes in web pages. The text does get picked up by webkit and all the events seem to be ok. However, there are two interesting issues:

    1. key strokes get repeated in the console when I exit the application (didn't verify if it happens on-the-fly or after - but looks like the same as your issue)
    2. when pressing/releasing the shift key, strange unicode characters are entered in the strings I am editing - very frustrating (they are not visible - but breaks some code I did).

  • I did not have a chance to dig into it again, but I just tested it is the same when the program is started with and without the X server.

  • It has sure been a few months since this was first asked, I wonder if any of you got around this problem....

    I'm running a Qt 5 QML app on a Raspberry Pi without running the Xserver and while all things seem to work alright I get nasty behavior such as the application quitting when Ctrl + C is pressed. And ultimately if you write something like "sudo reboot" you end up being able to reboot the RPi from within the app..

    I've tried having catching events in a Root element and setting the event as accepted, I've also tried redirecting the application's output to a file when running it but it just won't budge.

    I was thinking of looking into ways to completely disable the terminal (my application is supposed to run in a kind of "kiosk" mode so I wouldn't mind crippling the Linux underneath, but I still think there should be a way of doing it direclty from Qt, hopefully you guys managed to solve it...

    Thanks in advance,


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