WP7 LongListSelector - find control inside DataTemplate

I have a collection bound to a longlistselector. When a button in the applicationbar is clicked, I want to show a column that was previously hidden inside the longlistselecto开发者_开发百科r. How can I get access to the grid inside my datatemplate so I can toggle the column's visibility?

I tried the FindName method but it keeps returning null for the control I want. Am I missing something?

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Rather than finding the inside the template, how about binding the Visibility property of the 's contents to a property in your view model. Then all you need to do is change the view models property and the 's contents will show or hide.