/// <summary>
/// Asynchronously loads the image for this control.
/// </summary>
private async void OnPreviewImageLoaded(object sender, RoutedEventArgs e)
{
try
{
// Set our temporary placeholder first
var image = (Image)sender;
image.Source = Imaging.GetPlaceholderIcon();
// Now download the new image async.
var package = image.DataContext as IDownloadablePackage;
if (package?.Images == null || package.Images.Length <= 0)
{
return;
}
// Calculate actual rendered size.
var tokenSource = new CancellationTokenSource();
image.Unloaded += (o, args) =>
{
image.Loaded -= OnPreviewImageLoaded;
tokenSource.Cancel();
};
var dpiScale = VisualTreeHelper.GetDpi(image);
var desiredWidth = (int)(image.DesiredSize.Width * dpiScale.DpiScaleX);
// Select and decode appropriate image.
var uri = package.Images[0].SelectBasedOnWidth(desiredWidth);
BitmapImage?result = await Task.Run(async() =>
{
await using var memoryStream = new MemoryStream(await _cacheService.GetOrDownloadFileFromUrl(uri, _cacheService.ModPreviewExpiration, false, tokenSource.Token));
if (!tokenSource.IsCancellationRequested)
{
return(Imaging.BitmapFromStream(memoryStream, desiredWidth));
}
return(null);
}, tokenSource.Token);
if (!tokenSource.IsCancellationRequested)
{
image.Source = result;
}
}
catch (Exception)
{
// ignored
}
}