Catrobat.IDE.WindowsShared.Common.NavigationHelper.NavigationHelper C# (CSharp) Method

        public NavigationHelper(Page page)
        {
            this.Page = page;

            // When this page is part of the visual tree make two changes:
            // 1) Map application view state to visual state for the page
            // 2) Handle hardware navigation requests
            this.Page.Loaded += (sender, e) =>
            {
#if WINDOWS_PHONE_APP
                Windows.Phone.UI.Input.HardwareButtons.BackPressed += HardwareButtons_BackPressed;
#else
                // Keyboard and mouse navigation only apply when occupying the entire window
                if (this.Page.ActualHeight == Window.Current.Bounds.Height &&
                    this.Page.ActualWidth == Window.Current.Bounds.Width)
                {
                    // Listen to the window directly so focus isn't required
                    Window.Current.CoreWindow.Dispatcher.AcceleratorKeyActivated +=
                        CoreDispatcher_AcceleratorKeyActivated;
                    Window.Current.CoreWindow.PointerPressed +=
                        this.CoreWindow_PointerPressed;
                }
#endif
            };

            // Undo the same changes when the page is no longer visible
            this.Page.Unloaded += (sender, e) =>
            {
#if WINDOWS_PHONE_APP
                Windows.Phone.UI.Input.HardwareButtons.BackPressed -= HardwareButtons_BackPressed;
#else
                Window.Current.CoreWindow.Dispatcher.AcceleratorKeyActivated -=
                    CoreDispatcher_AcceleratorKeyActivated;
                Window.Current.CoreWindow.PointerPressed -=
                    this.CoreWindow_PointerPressed;
#endif
            };
        }