async void OnFolderListBoxSelectionChanged(object sender, SelectionChangedEventArgs args)
{
FolderItem folderItem = (sender as ListBox).SelectedItem as FolderItem;
if (folderItem == null)
{
displayBorder.Child = null;
return;
}
if (folderItem.DisplayGrid != null)
{
displayBorder.Child = folderItem.DisplayGrid;
return;
}
Grid displayGrid = new Grid();
folderItem.DisplayGrid = displayGrid;
displayBorder.Child = displayGrid;
StorageFolder storageFolder = folderItem.StorageFolder;
IReadOnlyList <StorageFile> storageFiles = await storageFolder.GetFilesAsync();
foreach (StorageFile storageFile in storageFiles)
{
StorageItemThumbnail thumbnail =
await storageFile.GetThumbnailAsync(ThumbnailMode.SingleItem);
BitmapSource bitmap = await LoadBitmapAsync(thumbnail);
if (bitmap == null)
{
continue;
}
// Create new Image element to display the thumbnail
Image image = new Image
{
Source = bitmap,
Stretch = Stretch.None,
Tag = ImageType.Thumbnail
};
// Create an initial CompositeTransform for the item
CompositeTransform xform = new CompositeTransform();
xform.TranslateX = (displayBorder.ActualWidth - bitmap.PixelWidth) / 2;
xform.TranslateY = (displayBorder.ActualHeight - bitmap.PixelHeight) / 2;
xform.TranslateX += 256 * (0.5 - rand.NextDouble());
xform.TranslateY += 256 * (0.5 - rand.NextDouble());
// Create the ManipulableContentControl for the Image
ManipulableContentControl manipulableControl = new ManipulableContentControl(xform)
{
Content = image,
Tag = storageFile
};
manipulableControl.ManipulationStarted += OnManipulableControlManipulationStarted;
// Put it in the Grid
displayGrid.Children.Add(manipulableControl);
}
}