diff options
Diffstat (limited to 'Xamarin.Forms.Platform.WinRT')
| -rw-r--r-- | Xamarin.Forms.Platform.WinRT/ImageRenderer.cs | 63 |
1 files changed, 50 insertions, 13 deletions
diff --git a/Xamarin.Forms.Platform.WinRT/ImageRenderer.cs b/Xamarin.Forms.Platform.WinRT/ImageRenderer.cs index 8798b20e..56026d18 100644 --- a/Xamarin.Forms.Platform.WinRT/ImageRenderer.cs +++ b/Xamarin.Forms.Platform.WinRT/ImageRenderer.cs @@ -17,6 +17,7 @@ namespace Xamarin.Forms.Platform.WinRT public class ImageRenderer : ViewRenderer<Image, Windows.UI.Xaml.Controls.Image> { bool _measured; + bool _disposed; public override SizeRequest GetDesiredSize(double widthConstraint, double heightConstraint) { @@ -32,10 +33,20 @@ namespace Xamarin.Forms.Platform.WinRT protected override void Dispose(bool disposing) { - if (Control != null) + if (_disposed) { - Control.ImageOpened -= OnImageOpened; - Control.ImageFailed -= OnImageFailed; + return; + } + + _disposed = true; + + if (disposing) + { + if (Control != null) + { + Control.ImageOpened -= OnImageOpened; + Control.ImageFailed -= OnImageFailed; + } } base.Dispose(disposing); @@ -55,7 +66,7 @@ namespace Xamarin.Forms.Platform.WinRT SetNativeControl(image); } - await UpdateSource(); + await TryUpdateSource(); UpdateAspect(); } } @@ -65,7 +76,7 @@ namespace Xamarin.Forms.Platform.WinRT base.OnElementPropertyChanged(sender, e); if (e.PropertyName == Image.SourceProperty.PropertyName) - await UpdateSource(); + await TryUpdateSource(); else if (e.PropertyName == Image.AspectProperty.PropertyName) UpdateAspect(); } @@ -94,7 +105,7 @@ namespace Xamarin.Forms.Platform.WinRT Element?.SetIsLoading(false); } - void OnImageFailed(object sender, ExceptionRoutedEventArgs exceptionRoutedEventArgs) + protected virtual void OnImageFailed(object sender, ExceptionRoutedEventArgs exceptionRoutedEventArgs) { Log.Warning("Image Loading", $"Image failed to load: {exceptionRoutedEventArgs.ErrorMessage}" ); Element?.SetIsLoading(false); @@ -107,6 +118,11 @@ namespace Xamarin.Forms.Platform.WinRT void UpdateAspect() { + if (_disposed || Element == null || Control == null) + { + return; + } + Control.Stretch = GetStretch(Element.Aspect); if (Element.Aspect == Aspect.AspectFill) // Then Center Crop { @@ -120,15 +136,40 @@ namespace Xamarin.Forms.Platform.WinRT } } - async Task UpdateSource() + protected virtual async Task TryUpdateSource() { + // By default we'll just catch and log any exceptions thrown by UpdateSource so we don't bring down + // the application; a custom renderer can override this method and handle exceptions from + // UpdateSource differently if it wants to + + try + { + await UpdateSource().ConfigureAwait(false); + } + catch (Exception ex) + { + Log.Warning(nameof(ImageRenderer), "Error loading image: {0}", ex); + } + finally + { + ((IImageController)Element)?.SetIsLoading(false); + } + } + + protected async Task UpdateSource() + { + if (_disposed || Element == null || Control == null) + { + return; + } + Element.SetIsLoading(true); ImageSource source = Element.Source; IImageSourceHandler handler; if (source != null && (handler = Registrar.Registered.GetHandler<IImageSourceHandler>(source.GetType())) != null) { - Windows.UI.Xaml.Media.ImageSource imagesource = null; + Windows.UI.Xaml.Media.ImageSource imagesource; try { @@ -138,10 +179,6 @@ namespace Xamarin.Forms.Platform.WinRT { imagesource = null; } - catch (Exception ex) - { - Log.Warning("Image Loading", $"Error updating image source: {ex}"); - } // In the time it takes to await the imagesource, some zippy little app // might have disposed of this Image already. @@ -155,7 +192,7 @@ namespace Xamarin.Forms.Platform.WinRT else { Control.Source = null; - Element?.SetIsLoading(false); + Element.SetIsLoading(false); } } } |