HiI am trying to create and start an animation in code instead of using xaml. When I use the Storyboard object(second example) nothing happens(There are no visible results of the animation), if I set animation's properties and start it without using the Storyboard object everything works normaly(first example). Below is the sample code which is put in the event handler for a button which is on the UserControl.//This works normalybtn_Click(object sender, RoutedEventArgs e){LinearGradientBrush mask = new LinearGradientBrush();GradientStop transparentStop = new GradientStop(Colors.Transparent, 0);GradientStop visibleStop = new GradientStop(Colors.Black, 0);mask.GradientStops.Add(transparentStop);mask.GradientStops.Add(visibleStop);this.OpacityMask = mask;DoubleAnimation visibleStopAnimation = new DoubleAnimation(0, 1.2, TimeSpan.FromSeconds(1.2), FillBehavior.HoldEnd);visibleStop.BeginAnimation(GradientStop.OffsetProperty, visibleStopAnimation);}//This doesn't workbtn_Click(object sender, RoutedEventArgs e){LinearGradientBrush mask = new LinearGradientBrush();GradientStop transparentStop = new GradientStop(Colors.Transparent, 0);GradientStop visibleStop = new GradientStop(Colors.Black, 0);mask.GradientStops.Add(transparentStop);mask.GradientStops.Add(visibleStop);this.OpacityMask = mask;Storyboard story = new Storyboard();story.Duration = TimeSpan.FromSeconds(1);DoubleAnimation visibleStopAnimation = new DoubleAnimation(0, 1, TimeSpan.FromSeconds(1), FillBehavior.HoldEnd);Storyboard.SetTarget(visibleStopAnimation, visibleStop);Storyboard.SetTargetProperty(visibleStopAnimation, new PropertyPath("(Offset)"));story.Children.Add(visibleStopAnimation);story.Begin();}Does anybody has any idea? Any advice will be appreciated!Uros