private void InitializeThumbnail()
{
if (IntPtr.Zero != _thumb)
{
// release the old thumbnail
ReleaseThumbnail();
}
if (IntPtr.Zero == Handle)
{
return;
}
// find our parent hwnd
_target = (HwndSource)HwndSource.FromVisual(this);
// if we have one, we can attempt to register the thumbnail
if (_target == null || 0 != DwmUtils.DwmRegisterThumbnail(_target.Handle, Handle, out this._thumb))
{
return;
}
DwmThumbnailProperties props = new DwmThumbnailProperties();
props.Visible = false;
props.SourceClientAreaOnly = false;
props.Opacity = (byte)(255 * this.Opacity);
props.Flags = ThumbnailFlags.Visible |
ThumbnailFlags.SourceClientAreaOnly |
ThumbnailFlags.Opacity;
DwmUtils.DwmUpdateThumbnailProperties(_thumb, ref props);
}
private void InitialiseThumbnail(IntPtr source)
{
if (IntPtr.Zero != thumb)
{
// release the old thumbnail
ReleaseThumbnail();
}
if (IntPtr.Zero != source)
{
// find our parent hwnd
target = (HwndSource)HwndSource.FromVisual(this);
// if we have one, we can attempt to register the thumbnail
if (target != null && 0 == DwmUtils.DwmRegisterThumbnail(target.Handle, source, out this.thumb))
{
DwmThumbnailProperties props = new DwmThumbnailProperties();
props.Visible = false;
props.SourceClientAreaOnly = this.ClientAreaOnly;
props.Opacity = (byte)(255 * this.Opacity);
props.Flags = ThumbnailFlags.Visible | ThumbnailFlags.SourceClientAreaOnly
| ThumbnailFlags.Opacity;
DwmUtils.DwmUpdateThumbnailProperties(thumb, ref props);
}
}
}