Question

Can someone explain the threading model in windows metro?
I really get confusion about this.

I know that the WWAHost.exe creates the first MTA (main thread?)
and we also have a UI thread(STA?) and some worker thread(STAorMTA?)

and only the main thread can update to UI thread.
So when user touch a button , and then what happened?
sry, my english is bad.

Answer 1

There’s a little about it in the CoreApplication class text:

The system creates this object as a singleton when it runs the app. It
is run as an Application Single-Threaded Apartment (ASTA). Threads
created from the app singleton, such as the view provider (seen in the
sample below), should be attributed as Multi-Threaded Apartment
(MTAThread).