Problems of handling Keys events

[stuvanya]

Hello!
I have main Item, and all windows, dialogs etc are children of it.
I have added into it two Key listeners:

    Keys.onPressed: {
        console.log("PRESSED");
        if (event.key === Qt.Key_Back) {
            event.accepted = true;
        }
    }

    Keys.onReleased: {
        console.log("RELEASED");
        if (event.key === Qt.Key_Back) {
            event.accepted = true;
            mainScreen.backPressed()
        }
    }

They triggers normally, until focus on some TextInput (Android Keyboard is shownig) and then tap back to close keyboard. How can I fix that?