Animated Progress Bar in WPF

WPF progress bars are conceptually the same as Windows progress bars; however, a very noticeable difference is that using standard coding techniques, the WPF Progress Bars do not update correctly while the application is processing.
Here i am going to give an example of animated progress bar in wpf. for this example i am using double animation in ellipse.

<Window x:Class="wpftheme.Window2"         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"         Title="Window2" Height="300" Width="300">     <Window.Resources>         <Storyboard x:Key="Storyboard1" RepeatBehavior="Forever">             <DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="ellipse" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[2].(RotateTransform.Angle)">                       <SplineDoubleKeyFrame KeyTime="00:00:02" Value="360"/>                   </DoubleAnimationUsingKeyFrames>         </Storyboard>     </Window.Resources>     <Window.Triggers>         <EventTrigger RoutedEvent="FrameworkElement.Loaded">             <BeginStoryboard Storyboard="{StaticResource Storyboard1}"/>         </EventTrigger>     </Window.Triggers     <Grid>         <Ellipse x:Name="ellipse" Margin="55,49,54,38" StrokeThickness="15" RenderTransformOrigin="0.5,0.5">             <Ellipse.RenderTransform>                   <TransformGroup>                     <ScaleTransform/>                              <SkewTransform/>                                <RotateTransform/>                 </TransformGroup>                </Ellipse.RenderTransform>             <Ellipse.Stroke>                  <LinearGradientBrush EndPoint="0.445,0.997" StartPoint="0.555,0.003">                                   <GradientStop Color="White" Offset="0"/>                              <GradientStop Color="#FF0052FF" Offset="1"/>                 </LinearGradientBrush>             </Ellipse.Stroke>         </Ellipse>     </Grid> </Window>