WPF Storyboard Animation Not Working

2019-05-29 14:44发布

问题:

I have my custom 3D model class (Model) which contains Visual3D element and a Storyboard (sb) to hold animations related to that model. I'm trying to rotate the Visual3D element using the Storyboard but unfortunately it's not working.

Here is the code snippet

public void AnimationRotate(Model model, double duration, double startTime, RepeatBehavior behaviour)
    {

        //Rotate transform 3D
        RotateTransform3D rotateTransform = new RotateTransform3D();

        //assign transform to the model
        model.Visual3D.Transform = Transform3DHelper.CombineTransform(model.Visual3D.Transform, rotateTransform);

        //define the rotation axis
        AxisAngleRotation3D rotateAxis = new AxisAngleRotation3D(new Vector3D(0, 0, 1), 180);

        //create 3D rotation animation
        Rotation3DAnimation rotateAnimation = new Rotation3DAnimation(rotateAxis, TimeSpan.FromSeconds(0.5));

        //rotation behaviour
        rotateAnimation.RepeatBehavior = behaviour;

        //start animation from time
        rotateAnimation.BeginTime = TimeSpan.FromSeconds(startTime);

        //begin animation - THIS WORKS FINE
       // rotateTransform.BeginAnimation(RotateTransform3D.RotationProperty, rotateAnimation);

        Storyboard.SetTargetProperty(rotateAnimation, new PropertyPath(RotateTransform3D.RotationProperty));
        Storyboard.SetTarget(rotateAnimation, rotateTransform);

        //add animation to the storyboard of the model
        model.sb.Children.Add(rotateAnimation);

        //BUT THIS APPROACH IS NOT WOKRING
        model.sb.Begin();

    }

回答1:

The problem is described in this answer.

Instead of using Storyboard.SetTarget you need to register a name for the transform and call Storyboard.SetTargetName. Furthermore you must call Storyboard.Begin(FrameworkElement) and pass a FrameworkElement with the appropriate name scope as parameter (this here).

RegisterName("RotateTransform", rotateTransform);
Storyboard.SetTargetName(rotateAnimation, "RotateTransform");
...
model.sb.Begin(this);

Also I guess you need to clear the Storyboard's Children somewhere, or create a new Storyboard whenever the animation is started.