Popup's in WinRT apps are really powerful to pop up content to prompt a user for some form of input. They are generally pretty straight forward to work with. They could be full screen, pinned to a corner, or you could open them relative to a button (or other element) the user interacts with. What happens when that button is near the edge of the screen, and the pop up opens off screen? Shortly, I'll introduce the AutoAlignedPopup, but first, let's start with the basics.
A Popup is a very basic element. It's essential a container object that has properties for user interaction, and contains a child UIElement.
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