On OS X, Cmd+R press must not add "r" to textfields

import QtQuick 2.3
import QtQuick.Controls 1.2

Rectangle {
    width: 360
    height: 360

    function refresh() {
        input1.text = ""
        input2.text = ""
        input3.text = ""
    }

    Keys.onPressed: {
        if (event.modifiers & Qt.ControlModifier)
        {
            if (event.key === Qt.Key_W)
            {
                Qt.quit()
            }

            if (event.key === Qt.Key_R)
            {
                refresh()
                event.accepted = true
            }
        }
    }

    Column {
        anchors.centerIn: parent

        TextEdit {
            id: input1
            text: "Cmd key test"
        }

        TextField {
            id: input2
            text: "README"
        }

        TextArea {
            id: input3
            text: "Cmd+R to refresh text\nCmd+W to close window"
        }

        Button {
            id: button
            text: "Unfocus all text fields"
            onClicked: button.forceActiveFocus()
        }
    }
}