private static ObjectAnimationUsingKeyFrames?GetAnimation(Image imageControl, BitmapSource source)
{
var animation = AnimationCache.GetAnimation(source, GetRepeatBehavior(imageControl));
if (animation != null)
{
return(animation);
}
if (!(GetDecoder(source, imageControl, out var gifMetadata) is GifBitmapDecoder decoder) || decoder.Frames.Count <= 1)
{
return(null);
}
var fullSize = GetFullSize(decoder, gifMetadata);
var index = 0;
animation = new ObjectAnimationUsingKeyFrames();
var totalDuration = TimeSpan.Zero;
BitmapSource?baseFrame = null;
foreach (var rawFrame in decoder.Frames)
{
var metadata = GetFrameMetadata(decoder, gifMetadata, index);
var frame = MakeFrame(fullSize, rawFrame, metadata, baseFrame);
var keyFrame = new DiscreteObjectKeyFrame(frame, totalDuration);
animation.KeyFrames.Add(keyFrame);
totalDuration += metadata.Delay;
switch (metadata.DisposalMethod)
{
case FrameDisposalMethod.None:
case FrameDisposalMethod.DoNotDispose:
baseFrame = frame;
break;
case FrameDisposalMethod.RestoreBackground:
baseFrame = IsFullFrame(metadata, fullSize) ? null : ClearArea(frame, metadata);
break;
case FrameDisposalMethod.RestorePrevious:
// Reuse same base frame
break;
default:
throw new ArgumentOutOfRangeException();
}
index++;
}
animation.Duration = totalDuration;
animation.RepeatBehavior = GetActualRepeatBehavior(imageControl, decoder, gifMetadata);
AnimationCache.AddAnimation(source, GetRepeatBehavior(imageControl), animation);
AnimationCache.IncrementReferenceCount(source, GetRepeatBehavior(imageControl));
return(animation);
}
static void ImageControlUnloaded(object sender, RoutedEventArgs e)
{
if (!(sender is Image imageControl))
{
return;
}
var source = GetAnimatedSource(imageControl);
if (source != null)
{
AnimationCache.DecrementReferenceCount(source, GetRepeatBehavior(imageControl));
}
var controller = GetAnimationController(imageControl);
controller?.Dispose();
}
private static void AnimatedSourceChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
{
if (!(o is Image imageControl))
{
return;
}
var oldValue = e.OldValue as ImageSource;
var newValue = e.NewValue as ImageSource;
if (ReferenceEquals(oldValue, newValue))
{
if (imageControl.IsLoaded)
{
var isAnimLoaded = GetIsAnimationLoaded(imageControl);
if (!isAnimLoaded)
{
InitAnimationOrImage(imageControl);
}
}
return;
}
if (oldValue != null)
{
imageControl.Loaded -= ImageControlLoaded;
imageControl.Unloaded -= ImageControlUnloaded;
AnimationCache.DecrementReferenceCount(oldValue, GetRepeatBehavior(imageControl));
var controller = GetAnimationController(imageControl);
controller?.Dispose();
imageControl.Source = null;
}
if (newValue == null)
{
return;
}
imageControl.Loaded += ImageControlLoaded;
imageControl.Unloaded += ImageControlUnloaded;
if (imageControl.IsLoaded)
{
InitAnimationOrImage(imageControl);
}
}
private static void RepeatBehaviorChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
{
if (!(o is Image imageControl))
{
return;
}
var source = GetAnimatedSource(imageControl);
if (source == null)
{
return;
}
if (!Equals(e.OldValue, e.NewValue))
{
AnimationCache.DecrementReferenceCount(source, (RepeatBehavior)e.OldValue);
}
if (imageControl.IsLoaded)
{
InitAnimationOrImage(imageControl);
}
}