/// <summary>
/// Override the thumbnail and peek bitmap.
/// By providing this bitmap manually, Thumbnail Window manager will provide the
/// Desktop Window Manager (DWM) this bitmap instead of rendering one automatically.
/// Use this property to update the bitmap whenever the control is updated and the user
/// needs to be shown a new thumbnail on the taskbar preview (or aero peek).
/// </summary>
/// <param name="hBitmap">A bitmap handle for the image to use.
/// <para>When the TabbedThumbnail is finalized, this class will delete the provided hBitmap.</para></param>
/// <remarks>
/// If the bitmap doesn't have the right dimensions, the DWM may scale it or not
/// render certain areas as appropriate - it is the user's responsibility
/// to render a bitmap with the proper dimensions.
/// </remarks>
internal void SetImage(IntPtr hBitmap)
{
// Before we set a new bitmap, dispose the old one
if (CurrentHBitmap != IntPtr.Zero)
{
ShellNativeMethods.DeleteObject(CurrentHBitmap);
}
// Set the new bitmap
CurrentHBitmap = hBitmap;
// Let DWM know to invalidate its cached thumbnail/preview and ask us for a new one
TaskbarWindowManager.InvalidatePreview(TaskbarWindow);
}
/// <summary>
/// Invalidates all the tabbed thumbnails. This will force the Desktop Window Manager
/// to not use the cached thumbnail or preview or aero peek and request a new one next time.
/// </summary>
/// <remarks>This method should not be called frequently.
/// Doing so can lead to poor performance as new bitmaps are created and retrieved.</remarks>
public void InvalidateThumbnails()
{
// Invalidate all the previews currently in our cache.
// This will ensure we get updated bitmaps next time
foreach (TabbedThumbnail thumbnail in _tabbedThumbnailCache.Values)
{
TaskbarWindowManager.InvalidatePreview(thumbnail.TaskbarWindow);
thumbnail.SetImage(IntPtr.Zero); // TODO: Investigate this, and why it needs to be called.
}
foreach (TabbedThumbnail thumbnail in _tabbedThumbnailCacheWPF.Values)
{
TaskbarWindowManager.InvalidatePreview(thumbnail.TaskbarWindow);
thumbnail.SetImage(IntPtr.Zero);
}
}