Strange behaviour of media element

Question

I'm making a media player with basic functions, but it is behaving strangely, when pause play or stop button is clicked following exception occurs 'System.NotSupportedException' Additional information: Cannot control media unless LoadedBehavior or UnloadedBehavior is set to Manual.

Required code and xaml is as follows:

XAML:

<MediaElement x:Name="VideoPreview" LoadedBehavior="Manual"  UnloadedBehavior="Stop" Width="auto" Height="250"  MediaOpened="Element_MediaOpened" MediaEnded="Element_MediaEnded" Source="{Binding SelectedItem.SourceUri, ElementName=VideoList}" Margin="5,5,5,5" Stretch="Fill"/>

Code behind:

void OnMouseDownPlayMedia(object sender, MouseButtonEventArgs args)
{         
    VideoPreview.Play();
}

// Pause the media. 
void OnMouseDownPauseMedia(object sender, MouseButtonEventArgs args)
{
    VideoPreview.Pause();
}

// Stop the media. 
void OnMouseDownStopMedia(object sender, MouseButtonEventArgs args)
{
    VideoPreview.Stop();
}

When either of the mouse events is clicked I get the exception.

Answer 1

The answer really is in the error text... Cannot control media unless LoadedBehavior or UnloadedBehavior is set to Manual. Therefore, your solution is to set either the MediaElement.LoadedBehavior or MediaElement.UnloadedBehavior property to a value of MediaState.Manual.

From the MediaElement.LoadedBehavior Property page on MSDN:

LoadedBehavior must be set to Manual in order to interactively control media with the Play, Pause, and Stop methods.

It's amazing what you can find out from MSDN.