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ImageGridView_ContainerContentChanging(ListViewBase sender,ContainerContentChangingEventArgs args){ if (args.InRecycleQueue) { var templateRoot = args.ItemContainer.ContentTemplateRoot as Grid; var image = templateRoot?.FindName("ItemImage") as Image; if (image is not null) { image.Source = null; } }#if WINDOWS if (args.Phase == 0) { args.RegisterUpdateCallback(ShowImage); args.Handled = true; }#else ShowImage(sender, args);#endif}The specialized callback is now only registered using ContainerContentChangingEventArgs.RegisterUpdateCallback() if the platform is Windows. Otherwise, the ShowImage method is called directly. We'll also need to make changes to the ShowImage method to work alongside the changes made to the ImageGridView_ContainerContentChanging method. Replace the ShowImage method in the MainPage.xaml.cs file with the following code:private async void ShowImage(ListViewBase sender, ContainerContentChangingEventArgs args){ if (#if WINDOWS args.Phase == 1#else true#endif ) { // It's phase 1, so show this item's image. var templateRoot = args.ItemContainer.ContentTemplateRoot as Grid; var image = templateRoot?.FindName("ItemImage") as Image; var item = args.Item as ImageFileInfo;#if WINDOWS if (image is not null && item is not null) { image.Source = await item.GetImageThumbnailAsync(); }#else if (item is not null) { await item.GetImageSourceAsync(); }#endif }}Again, preprocessor directives ensure that the ContainerContentChangingEventArgs.Phase property is only used on platforms where it is supported. We make use of the previously unused GetImageSourceAsync() method to load the image files into the GridView on platforms other than Windows. At this point, we'll accommodate the changes made above by editing the ImageFileInfo class.Creating a separate code path for other platformsUpdate ImageFileInfo.cs to include a new property called ImageSource that will be used to load the image file.public BitmapImage? ImageSource { get; private set; }Because platforms like the web do not support advanced image file properties that are readily available on Windows, we'll add a constructor overload that does not require an ImageProperties typed parameter. Add the new overload after the existing one using the following code:public ImageFileInfo(StorageFile imageFile, string name, string type){ ImageName = name; ImageFileType = type; ImageFile = imageFile;}This constructor overload is used to construct an ImageFileInfo object on platforms other than Windows. Since we did this, it makes sense to make the ImageProperties property nullable. Update the ImageProperties property to be nullable using the following code:public ImageProperties? ImageProperties { get; }Update the GetImageSourceAsync method to use the ImageSource property instead of only returning a BitmapImage object. Replace the GetImageSourceAsync method in the ImageFileInfo.cs file with the following code:public async Task GetImageSourceAsync(){ using IRandomAccessStream fileStream = await ImageFile.OpenReadAsync(); // Create a bitmap to be the image source. BitmapImage bitmapImage = new(); bitmapImage.SetSource(fileStream); ImageSource = bitmapImage; PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(ImageSource))); return bitmapImage;}To prevent getting the value of ImageProperties when it's null, make the following changes:Modify the ImageDimensions property to use the null conditional operator:public string ImageDimensions => $"{ImageProperties?.Width} x {ImageProperties?.Height}";Change the ImageTitle property to use the null conditional operator:public string ImageTitle{ get => string.IsNullOrEmpty(ImageProperties?.Title) ? ImageName : ImageProperties?.Title; set { if (ImageProperties is not null) { if (ImageProperties.Title != value) { ImageProperties.Title = value; _ = ImageProperties.SavePropertiesAsync(); OnPropertyChanged(); } } }}Change ImageRating to not rely on ImageProperties by generating a random star rating for demonstration purposes:public int ImageRating{ get => (int)((ImageProperties?.Rating == null || ImageProperties.Rating == 0) ?

CaptureMouse() Attempts to force capture of the mouse to this element. (Inherited from UIElement) CaptureStylus() Attempts to force capture of the stylus to this element. (Inherited from UIElement) CaptureTouch(TouchDevice) Attempts to force capture of a touch to this element. (Inherited from UIElement) CheckAccess() Determines whether the calling thread has access to this DispatcherObject. (Inherited from DispatcherObject) ClearValue(DependencyProperty) Clears the local value of a property. The property to be cleared is specified by a DependencyProperty identifier. (Inherited from DependencyObject) ClearValue(DependencyPropertyKey) Clears the local value of a read-only property. The property to be cleared is specified by a DependencyPropertyKey. (Inherited from DependencyObject) CoerceValue(DependencyProperty) Coerces the value of the specified dependency property. This is accomplished by invoking any CoerceValueCallback function specified in property metadata for the dependency property as it exists on the calling DependencyObject. (Inherited from DependencyObject) EndInit() Indicates that the initialization process for the element is complete. (Inherited from FrameworkElement) Equals(Object) Determines whether a provided DependencyObject is equivalent to the current DependencyObject. (Inherited from DependencyObject) FindCommonVisualAncestor(DependencyObject) Returns the common ancestor of two visual objects. (Inherited from Visual) FindName(String) Finds an element that has the provided identifier name. (Inherited from FrameworkElement) FindResource(Object) Searches for a resource with the specified key, and throws an exception if the requested resource is not found. (Inherited from FrameworkElement) Focus() Attempts to set focus to this element. (Inherited from UIElement) GetAnimationBaseValue(DependencyProperty) Returns the base property value for the specified property on this element, disregarding any possible animated value from a running or stopped animation. (Inherited from UIElement)

The object that gets focus when a user presses the Directional Pad (D-pad) up. (Inherited from Control) XYFocusUpNavigationStrategy Gets or sets a value that specifies the strategy used to determine the target element of an up navigation. (Inherited from UIElement) Methods AddHandler(RoutedEvent, Object, Boolean) Adds a routed event handler for a specified routed event, adding the handler to the handler collection on the current element. Specify handledEventsToo as true to have the provided handler be invoked even if the event is handled elsewhere. (Inherited from UIElement) ApplyTemplate() Loads the relevant control template so that its parts can be referenced. (Inherited from Control) Arrange(Rect) Positions child objects and determines a size for a UIElement. Parent objects that implement custom layout for their child elements should call this method from their layout override implementations to form a recursive layout update. (Inherited from UIElement) ArrangeOverride(Size) Provides the behavior for the "Arrange" pass of layout. Classes can override this method to define their own "Arrange" pass behavior. (Inherited from FrameworkElement) CancelDirectManipulations() Cancels ongoing direct manipulation processing (system-defined panning/zooming) on any ScrollViewer parent that contains the current UIElement. (Inherited from UIElement) CapturePointer(Pointer) Sets pointer capture to a UIElement. Once captured, only the element that has capture will fire pointer-related events. (Inherited from UIElement) ClearValue(DependencyProperty) Clears the local value of a dependency property. (Inherited from DependencyObject) FindName(String) Retrieves an object that has the specified identifier name. (Inherited from FrameworkElement) FindSubElementsForTouchTargeting(Point, Rect) Enables a UIElement subclass to expose child elements that assist with resolving touch targeting. (Inherited from UIElement) Focus(FocusState) Attempts to set the focus on the control. (Inherited from Control) GetAnimationBaseValue(DependencyProperty) Returns any base value established for a dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject) GetBindingExpression(DependencyProperty) Returns the BindingExpression that represents the binding on the specified property. (Inherited from FrameworkElement) GetChildrenInTabFocusOrder() Enables a UIElement subclass to expose child elements that take part in Tab focus. (Inherited from UIElement) GetTemplateChild(String) Retrieves the named element in the instantiated ControlTemplate visual tree. (Inherited from Control) GetValue(DependencyProperty) Returns the current effective value of a dependency property from a DependencyObject. (Inherited from