/// <summary>
/// Starts an animation to a particular value on the specified dependency property.
/// You can pass in an event handler to call when the animation has completed.
/// </summary>
public static void StartAnimation(UIElement animatableElement, DependencyProperty dependencyProperty, Visibility toValue, double animationDurationSeconds, EventHandler completedEvent)
{
ObjectAnimationUsingKeyFrames objanimation = new ObjectAnimationUsingKeyFrames();
DiscreteObjectKeyFrame dobjf = new DiscreteObjectKeyFrame(toValue, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(0)));
objanimation.BeginTime = TimeSpan.FromMilliseconds(0);
objanimation.Duration = TimeSpan.FromMilliseconds(animationDurationSeconds);
objanimation.KeyFrames = new ObjectKeyFrameCollection()
{
dobjf
};
objanimation.Completed += delegate(object sender, EventArgs e)
{
//
// When the animation has completed bake final value of the animation
// into the property.
//
animatableElement.SetValue(dependencyProperty, animatableElement.GetValue(dependencyProperty));
CancelAnimation(animatableElement, dependencyProperty);
if (completedEvent != null)
{
completedEvent(sender, e);
}
};
objanimation.Freeze();
objanimation.BeginAnimation(dependencyProperty, objanimation);
}
private static void InitAnimationOrImage(Image imageControl)
{
BitmapSource source = GetAnimatedSource(imageControl) as BitmapSource;
bool isInDesignMode = DesignerProperties.GetIsInDesignMode(imageControl);
bool animateInDesignMode = GetAnimateInDesignMode(imageControl);
bool shouldAnimate = !isInDesignMode || animateInDesignMode;
// For a BitmapImage with a relative UriSource, the loading is deferred until
// BaseUri is set. This method will be called again when BaseUri is set.
bool isLoadingDeferred = IsLoadingDeferred(source);
if (source != null && shouldAnimate && !isLoadingDeferred)
{
GifFile gifMetadata;
var decoder = GetDecoder(source, out gifMetadata) as GifBitmapDecoder;
if (decoder != null && decoder.Frames.Count > 1)
{
int index = 0;
var 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(source, 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 = null;
break;
case FrameDisposalMethod.RestorePrevious:
// Reuse same base frame
break;
}
index++;
}
animation.Duration = totalDuration;
animation.RepeatBehavior = GetActualRepeatBehavior(imageControl, decoder, gifMetadata);
animation.Completed += delegate
{
imageControl.RaiseEvent(
new RoutedEventArgs(AnimationCompletedEvent, imageControl));
};
animation.Freeze();
if (animation.KeyFrames.Count > 0)
{
// For some reason, it sometimes throws an exception the first time... the second time it works.
TryTwice(() => imageControl.Source = (ImageSource)animation.KeyFrames[0].Value);
}
else
{
imageControl.Source = decoder.Frames[0];
}
imageControl.BeginAnimation(Image.SourceProperty, animation);
return;
}
}
imageControl.Source = source;
}
