Why cant a thread that is not the UI thread access the view?

Question

I know that no thread can access the current view unless it is the UI Thread. I am wondering why? Why does it matter which thread is changing the view? Is it a security reason?

Answer 1

Security isn't the only UI thread is the only thread that can access the Views. The main reason is that the code behind the views probably isn't thread safe. This means that there are no guarantees that data won't get corrupted if you have multiple threads reading and writing to common variables.

Check out this great wikipedia article about thread safety.