Unable to retrieve the swiped Filedialog

import QtQuick.Dialogs 1.3   // or import Qt.labs.platform 1.0

ApplicationWindow {
    id: window
    width: 400
    height: 400
    visible: true

    FileDialog {
           id: fileDialog
           visible: false
           title: "Select a Image"
       }

    Button {
      id: openButton
      anchors.centerIn: parent
      text: "Open"
      onClicked: fileDialog.visible = true
    }
}