In my Windows Phone app,I want to turn my current page unable in gray and show a textbox in foreground
Like the title said,how may i turn the grid(or page) and the components in it into background  gray and unable and show a new component in foreground.
It's a common effect in the web page.
    
Please answer in detail better with sample code.Thank you very much.
In my Windows Phone app,I want to turn my current page unable in gray and show a textbox in foreground
===

Like the title said,how may i turn the grid(or page) and the components in it into background  gray and unable and show a new component in foreground.
It's a common effect in the web page.
    
Please answer in detail better with sample code.Thank you very much.