Show/Hide Keyboard programmatically on windows8

Question

I am trying to show/hide keyboard on a Windows Metro app programmatically. I initially thought I could do it using a collapsed textbox and setting focus on it. But it seems

Answer 1

Just put a TextBox and hide it. Set the IsReadOnly = true and set the tab index of the TextBox to 0, so keyboard will focus on that TextBox but it realize TextBox is readonly and it will not poped up. :)