Storyboard targeting multiple objects, using SetTarget method, doesn't work

Question

Can anyone help me trying to find out why this doesn't work.

The brushes variable contains a pre-filled list of brushes. If I try to apply the BeginAnimation directly during the iteration, it works fine. But has a great overhead starting each animation separately...

So I was trying to put all the animations in a single storyboard, and fire them all at once...

var storyBoard = new Storyboard();           
var duration = new Duration(TimeSpan.FromMilliseconds(time));
foreach (Brush brush in brushes) 
{
    var animation = new DoubleAnimation(toValue, duration);

    storyBoard.Children.Add(animation);

    Storyboard.SetTargetProperty(animation, new PropertyPath(Brush.OpacityProperty));
    Storyboard.SetTarget(animation, brush);
}

storyBoard.Begin();

This code simply does nothing (that I can see...).

Edit: Still not sure of what is problem with the SetTarget method, either a bug or I'm just not using as it should be. Anyway I solved the problem generating unique names for my brushes at runtime and using the SetTargetName method.

Shouldn't you be pathing to the property that contains the brush and then the brush opacity? Something like new PropertyPath("(Shape.Fill).(SolidColorBrush.Opacity)") and then you'd see something closer to StoryBoard.SetTarget(animation, this) on the next line? I'm a beginner at best but this seems to be part of the problem. You want to change the brush of a property on an object, not the brush itself as the target (which I think you can't do anyway) — Marc

Y.Yanavichus Y.Yanavichus · Accepted Answer · 2011-02-24T13:19:06

Try to use Storyboard.SettargetName method instead of Storyboard.SetTarget. I prepared working sample for you:

var brushes = new string[] { "br1", "br2", "br3" };
var sb = new Storyboard();
var dur = new Duration(TimeSpan.FromMilliseconds(500.0));
double toValue = 1.0;

foreach (var brush in brushes)
{
  var anim = new DoubleAnimation(toValue, dur);
  Storyboard.SetTargetName(anim, brush);
  Storyboard.SetTargetProperty(anim, new PropertyPath("(0)", new DependencyProperty[] { Brush.OpacityProperty }));
  sb.Children.Add(anim);
}         

sb.Begin(this);

Remember, that in this case you also should set a Namescope as parameter for Storyboard.Begin method.

See also: Another answers on the Stackoverflow.

Storyboard targeting multiple objects, using SetTarget method, doesn't work

1 Answers