Qt QML - 处理导航按钮？

Question

Context:

Qt QML 5.6

I could not find related documentation to handle the Android navigation buttons in my QML app (triangle, square and circle, at the bottom of the screen).

Currently, when touching them, it just puts my app in the background. I would like to give them some logic.

Question:

Is it possible to manage those buttons in QML? Or will I have to deal with a c++ event handler? (If so, which code should one look after?)

Thanks

Answer 1

Poor man's solution:

Within the Window or application window scope, use

    onClosing: {
      do_what_you_need()
      close.accepted = false
    }

In do_what_you_need() , you may call Qt.quit if it is ok.

Answer 2

It is possible to manage these buttons from the QML. In QML, those key presses are handled exactly like key presses on a keyboard. For example, Qt.Key_Back refers to the back key(triangle) and Qt.Key_Home refers to the home key(square). Here is an example of listening for the home key in QML:

Keys.onPressed: {
   if (event.key == Qt.Key_Home) {
      console.log("Square button(home) pressed");
   }
}

For more on the key enumerations in Qt, see this documentation: http://doc.qt.io/qt-5/qt.html#Key-enum

Answer 3

For completeness, example with ignoring the back button (do not minimize the app)

focus: true
Keys.onPressed: {
   if (event.key == Qt.Key_Back) {
      event.accepted = true
   }
}