Sliverlight change the scene

I study the sliverlight change the scene method today.

I found the this easy job, because I think this isn't easy before.

So I show step to you :

1) modify the "app.xaml"

private void Application_Startup(object sender, StartupEventArgs e)
{
Grid g = new Grid();
this.RootVisual = g;
MainPage p = new MainPage();
g.Children.Add(p);
}

2) modify your page(scene)

for example: the mainPage.xaml

private void myButton_Click(object sender, RoutedEventArgs e)
{

Grid root = Application.Current.RootVisual as Grid;
if (root != null)
{
root.Children.RemoveAt(0);
root.Children.Add(new Page1());  // change current page to page1
}
}