How to show a preview of item template on Windows Phone Designer?

I'm designing an item template for a ListView but it is not shown on the designer.

I think that is because the ItemsSource is not set at the design-time, I set the ItemsSource at run-time only.

So is there a way to tell the designer emulate data for ItemsSource or whatever to show the preview? Currently, I have to run the app to see the result or copy content of ItemTemplate to outside of ListView to see the preview then copy back later.

Solution

Guess I should have just put it as an answer.

In VS, right-click your ListView in the Document Outline and choose "Edit Template -> Edit Generated Items" or the same in Blend.

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Then to toggle back out of there to your parent view hit the little icon in the top left corner of the document outline that looks like an upward pointing arrow on a bar

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