How to clear already sent notification message

I've a working notifications part in my project. And I want to give user to disable notifications in app itself. Once user checks this option, I bring tile image and title to original state. Even this part works fine. Count can be removed by sending 0, But i didn't understand how to remove already sent message, esp:

<wp:BackContent> </wp:BackContent>

I tried sending empty message but it didn't 开发者_如何转开发work. Any idea, how to clear this message on tile?

See this post on the AppHub: How do I reset a flipping Mango Tile after push notification?

Here is the answer: Need to send "clear", if you want to clear anything. Very intuitive but not documented well.

<wp:BackBackgroundImage Action=”Clear”></wp:BackBackgroundImage>

<wp:BackTitle Action=”Clear”></wp:BackTitle>

<wp:BackContent Action=”Clear”></wp:BackContent>