Positioning Popup Menus in Windows 8 Metro

Often when building Windows 8 apps you'll want to provide a menu of options from the app bar, this may be a list of different ways to sort or filter the data. For these simple menus WinRT provides the PopupMenu control (for more complicated popup user interfaces I recommend the Flyout control from the Callisto library), these menus are very easy to create by creating UI Commands and appending them to the menus Commands collection.

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