Cannot set property System.Windows.EventTrigger.RoutedEvent in Silverlight 4

Question

The above exception is thrown for this XAML application for Silverlight 4 application:

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="NewtonsCradle.MainPage"
    Width="640" Height="480">
    <StackPanel Orientation="Horiontal">
        <TextBlock Height="100" Name="TestText">Test</TextBlock>
        <StackPanel.Triggers>
            <EventTrigger RoutedEvent="Loaded">
                <BeginStoryboard>
                    <Storyboard>
                        <DoubleAnimation Storyboard.TargetName="TestText" 
                                         Storyboard.TargetProperty="Height" 
                                         To="500"
                                         Duration="0:0:1"/>
                    </Storyboard>
                </BeginStoryboard>
            </EventTrigger>
        </StackPanel.Triggers>
    </StackPanel>

</UserControl>

Code behind:

    using System.Windows.Controls;

namespace NewtonsCradle
{
    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            // Required to initialize variables
            InitializeComponent();

        }
    }
}

What? For me, this seems quite reasonable based on the WPF background.

Answer 1

I think no one answered this question, but fix a usage error

You need to actually put event triggers in the control you are animating, and also specify the full path to the event instead of "Loaded" use Border.Load

 <Border.Triggers>
                    <EventTrigger RoutedEvent="Border.Loaded">
                        <EventTrigger.Actions>
                            <BeginStoryboard>
                                <Storyboard>
                                    <DoubleAnimation Storyboard.TargetProperty="Height"  From="0" To="Auto" Duration="0:0:1" Storyboard.TargetName="Border1"/>
                                </Storyboard>
                            </BeginStoryboard>
                        </EventTrigger.Actions>
                    </EventTrigger>
</Border.Triggers>