How to trigger an event in a silverlight animation by keyframe?

Question

I need to call a method when the animation hits a specific keyframe. Is it possible to trigger an event when an animation hits a specific keyframe? If there is no better way to trigger an event at a specific time?

Answer 1

Silverlight dates are very limited when it comes to events. As far as I can tell, only the Completed event is supported. What you could do is have two timelines inside the same storyboard, where the second timeline updates the related property that you can observe.

Maybe something like:

<Storyboard> <DoubleAnimationusingKeyFrames ... /> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="TriggerEvent"> <ObjectKeyFrame KeyTime="00:00:01" Value="True" /> <ObjectAnimationUsingKeyFrames> </Storyboard> 

Then, in your code for the control, define a dependency property called a TriggerEvent of type Boolean. When it changes to true, call your method.

Another option, however , which is probably best, is to split the original animation into two parallel graphs and connect the Completed processed event handler to the first timeline (which you would use to call your method), then on the second timeline use the BeginTime property to synchronize two animations, so that the second one gets the same way as the first one.

 <Storyboard> <!-- Timeline 1 --> <DoubleAnimationusingKeyFrames Completed="MyCompletedHandler" ... /> <!-- Timeline 2 --> <DoubleAnimationUsingKeyFrames BeginTime="00:00:01" ... /> </Storyboard>