Currently, the following Item will not receive any key events:

    import QtQuick 2.2
    import QtQuick.Controls 1.2

    ApplicationWindow {
        visible: true
        width: 200
        height: 200

        Item {
            focus: true
            anchors.fill: parent

            Keys.onLeftPressed: textItem.text = "Left"
            Keys.onRightPressed: textItem.text = "Right"
            Keys.onPressed: {
                if (event.key === Qt.Key_Home) {
                    textItem.text = "Home";
                } else if (event.key === Qt.Key_End) {
                    textItem.text = "End";
                }
            }

            Text {
                id: textItem
                anchors.centerIn: parent
            }
        }
    }

Using Window instead of ApplicationWindow does, however.
ApplicationWindow can behave the same if we ensure that the panel has
focus set to true. When the panel has focus, the contentItem can
receive focus.

[ChangeLog][ApplicationWindow] Top level items now receive focus when
their focus property is set to true, in the same way that top level
items of Window do.

Change-Id: I16ef1632fc6df1989015e62e8683b6cd7c5be8a6
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Reviewed-by: Liang Qi <liang.qi@digia.com>