Custom window draging handler

[Noturnoz]

Hello, I have made following window dragging handler, but the problem is that the moving is not smooth. The window is "shaking" when I move it.

MouseArea {
    anchors.fill: parent

    property variant clickPos: "1,1"

    onPressed: {
        clickPos  = Qt.point(mouse.x,mouse.y)
    }

    onPositionChanged: {
        var delta = Qt.point(mouse.x-clickPos.x, mouse.y-clickPos.y)
        rootApplicationWindow.x += delta.x;
        rootApplicationWindow.y += delta.y;
    }

    propagateComposedEvents: true
}

I am using this custom handler, because I am using FramelessWindow, so I can make whole UI custom, without native toolbars etc.

Can someone tell me, if it is possible to create custom handler, which won't shake the window when draggin?