Benjamin Roux

#region Dependency Properties

public bool IsBusy

{

    get { return (bool)GetValue(IsBusyProperty); }

    set 

    { 

        SetValue(IsBusyProperty, value);

        ChangeState();

    }

}

// Using a DependencyProperty as the backing store for IsBusy.  This enables animation, styling, binding, etc...

public static readonly DependencyProperty IsBusyProperty =

    DependencyProperty.Register("IsBusy", typeof(bool), typeof(BusyPointer), new PropertyMetadata(new PropertyChangedCallback(OnBusyChanged)));

private static void OnBusyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)

{

    ((BusyPointer)sender).IsBusy = (bool)e.NewValue;

}

#endregion

#region Initialization

public BusyPointer()

{

    this.DefaultStyleKey = typeof(BusyPointer);

}

#endregion

#region Methods

private void ChangeState()

{

    if (IsBusy) VisualStateManager.GoToState(this, "Busied", true);

    else VisualStateManager.GoToState(this, "Normal", true);

}

#endregion

<Style TargetType="local:BusyPointer">

    <Setter Property="Template">

        <Setter.Value>

            <ControlTemplate TargetType="local:BusyPointer">

                <Grid x:Name="LayoutRoot" Background="Transparent">

                    <vsm:VisualStateManager.VisualStateGroups>

                        <vsm:VisualStateGroup x:Name="CommonStates">

                            <vsm:VisualState x:Name="Normal" />

                            <vsm:VisualState x:Name="Busied">

                                <Storyboard>

                                    <DoubleAnimationUsingKeyFrames Storyboard.TargetName="VisualElement" Storyboard.TargetProperty="(UIElement.RenderTransform).Angle" RepeatBehavior="Forever">

                                        <SplineDoubleKeyFrame KeyTime="0:0:1" Value="360" />

                                    </DoubleAnimationUsingKeyFrames>

                                </Storyboard>

                            </vsm:VisualState>

                        </vsm:VisualStateGroup>

                    </vsm:VisualStateManager.VisualStateGroups>

                    <Ellipse Width="25" Height="25" StrokeThickness="5.5" x:Name="VisualElement">

                        <Ellipse.Stroke>

                            <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">

                                <GradientStop Color="#FF096475" Offset="0.571"/>

                                <GradientStop Color="#FFA8FCFC" Offset="1"/>

                            </LinearGradientBrush>

                        </Ellipse.Stroke>

                        <Ellipse.RenderTransform>

                            <RotateTransform CenterX="12.5" CenterY="12.5" />

                        </Ellipse.RenderTransform>

                    </Ellipse>

                </Grid>

            </ControlTemplate>

        </Setter.Value>

    </Setter>

</Style>