How to license my Android application?

I am just about to complete my Android application. Now I want to upload my application to the Android market for paid application. For that I have read the document f开发者_开发问答rom the Android site:

android licensing

But I want to see any demo or project that has done such licensing. I have seen the demo on the android developer site of mainactivity. But there the handler is given and I want to implement that code into mymainactivity of the project. In mymainactivity there is a splash screen in the start of the application, and I have set one handler for it. So that's why I need an example, to see how to implement the licensing in our own application.

Another thing I want to know is, is this compulsory to implement Android licensing in order to upload a paid application to the Android market?

Is it possible to set the application as paid without implementing the licensing of the Android application?

If so and there are any demos available, please give me a link to that.