public MainPage()
        {
            this.InitializeComponent();

            ShowStatusBar();

            if (DeviceTypeHelper.GetDeviceFromFactorType() == DeviceFromFactorType.Phone)
            {
                Debug.WriteLine("current:" + _currentViewHeight + "; initial:" + InitialViewHeight + ";  BarStatus:" + IsSystemVirtualButtonBarShow);

                ApplicationView.GetForCurrentView().VisibleBoundsChanged += (sender, e) =>
                {
                    _currentViewHeight = ApplicationView.GetForCurrentView().VisibleBounds.Height;

                    Debug.WriteLine("current:" + _currentViewHeight + "; initial:" + InitialViewHeight + ";  BarStatus:" + IsSystemVirtualButtonBarShow);

                    MessagingCenter.Send <YahooTWBuy.Pages.MainPage, bool>((YahooTWBuy.Pages.MainPage)MainApp.MainPage,
                                                                           "UWP_SystemVirtualButtonBarStatus", IsSystemVirtualButtonBarShow);
                };
            }

            LoadApplication(MainApp);
        }