Why doesn't this rotate? (WPF, Storyboard)

Peter

17y15k

I'm trying to learn how to implement Storyboards in the code-behind.   I have a simple rotation of some label text that works fine in XAML . . .


                                            Storyboard.TargetName="lblHello"
                      Storyboard.TargetProperty="(TextBlock.RenderTransform).(RotateTransform.Angle)"
                      From="0"
                      To="360"
                      Duration="0:0:0.5"
                      RepeatBehavior="4x" />


But when I try to implement it in a button handler in the code-behind it doesn't rotate (nothing seems to happen) . . .

            Storyboard sb = new Storyboard();

            DoubleAnimation da_AngleAnimation
               = new DoubleAnimation();

            da_AngleAnimation.From = 360;
            da_AngleAnimation.To = 0;
            da_AngleAnimation.Duration
              = new Duration(new TimeSpan(0, 0, 0, 0, 500));
            da_AngleAnimation.RepeatBehavior = new RepeatBehavior(4);

            PropertyPath PropP = new PropertyPath(RotateTransform.AngleProperty);

            Storyboard.SetTargetName(da_AngleAnimation, lblHello.Name);
            Storyboard.SetTargetProperty(da_AngleAnimation,PropP);

            sb.Children.Add(da_AngleAnimation);

            this.BeginStoryboard(sb);

What am I doing wrong?   Thanks in advance!!!

2 Replies

Know the answer? Post it — somebody with the same question will find it here.

Peter17y ago
Galasoft is where I got the original code. But I couldn't get his example to work without errors , even when I downloaded his example code.

But that's OK - I rewrote the app from scratch and figured out a solution on my own - it's based on the recognition that RotateTransform is not a direct property of a TextBlock. To make the rotation angle accessible, first do this in the XAML:












   Then in the code-behind, you can do it this . . .

           Storyboard sb = new Storyboard();

            // Create a DoubleAnimation to animate the angle . . .
            DoubleAnimation myDoubleAnimation = new DoubleAnimation();
            myDoubleAnimation.From = 0;
            myDoubleAnimation.To = 180;
            myDoubleAnimation.Duration = new Duration(TimeSpan.FromMilliseconds(2500));

            Storyboard.SetTargetName(myDoubleAnimation, "rtAngle");
            PropertyPath PropP = new PropertyPath(RotateTransform.AngleProperty);
            Storyboard.SetTargetProperty(myDoubleAnimation, PropP);

            sb.Children.Add(myDoubleAnimation);
            sb.Begin(this.textBlock1);

Note that my original code also had an error in the invocation of the animation, now fixed.
Sanjay Chauhan17y ago
Hi,

Take the reference of this article
http://www.galasoft.ch/mydotnet/articles/article-2006102701.aspx