[RESOLVED] Help WPF Slide Transition Effect between Views

[jedihok]

dear Master,

after searching and searching on internet, i almost figure this out. By some references from expert I manage to design 'MDI' and show the child form in mainform. What i want is show animation when child form shown on mainform (slide transition effect).
On my project I have :
1. mainwindow.xaml
2. page1.xaml (usercontrol)

the XAML for mainwindow as follow :

<Window x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="525">
    <Grid HorizontalAlignment="Left" Height="38" VerticalAlignment="Top" Width="525" Margin="0,0,-8,0">
        <Grid.Resources>
            <Storyboard x:Key="TransformImage">
                <DoubleAnimation
        Storyboard.TargetName="page1"
        Storyboard.TargetProperty="RenderTransform.(TranslateTransform.X)"
        By="100" Duration="0:0:3">
                </DoubleAnimation>
            </Storyboard>
        </Grid.Resources>
        <Grid.Triggers>
            <EventTrigger RoutedEvent="Button.Click" SourceName="btnClick">
                <BeginStoryboard Storyboard="{StaticResource TransformImage}"/>
            </EventTrigger>
        </Grid.Triggers>
        
        <StackPanel x:Name="Stk" HorizontalAlignment="Left" Height="281" Margin="-1,40,0,-283" VerticalAlignment="Top" Width="519"/>
        <Button x:Name="btnClick" Content=" Show Child" HorizontalAlignment="Left" Margin="10,10,0,6" Width="75" Click="Button_Click"/>
    </Grid>
</Window>

I want to show page1.xaml using slide transition effect, but I got error when I pressed BtnClick where page1.xaml not exist within mainform.xaml

Please help me.

regards