I'm slowly getting the hang of unified applications. Most of the time I'm having to forget how the phone does things, and pick up some Windows 8 habits. The busy indicator is a case in point. Using it is very easy, but it is different from the phone and so I thought I'd blog it here in case I forget. You can get a rather nice animated ring display like the one above by simply adding it to the XAML in your page:
<ProgressRing Name="BusyProgressRing" IsActive="False"></ProgressRing>
Then, in your program, you can just turn it on and off when you start something that might take a while to complete.
BusyProgressRing.IsActive = true;
I've written a stupidly simple unified app that lets you start and stop the ring displaying at the touch of a button. You can find it here.
This form of display is used when your program is doing something that will take a while to complete, and you don't know how long it will be. I use it when I'm setting up Bluetooth connections.