The Flyout control in JavaScript is handy for the Settings pane and for button Flyout extensions. But where is the Flyout control for WinRT XAML?
The control you are looking for is called Popup in XAML. Unlike the JavaScript implementation of Flyout, it is up to you location the subject button and position the Popup near it.
Look: http://blog.jerrynixon.com/2012/08/how-to-create-windows-8-settings-pane.html
use Callisto control toolkit, it has flyout control
来源：https://stackoverflow.com/questions/10965886/where-is-the-flyout-control-in-winrt-xaml