How to change the label(Android)?

I had writen a simple Android project. The main Activity has a gallery. Different pictures have differndt开发者_StackOverflow中文版 Activity. If I click one image, I would go to another Activity. The question is that how can I change the label, if the Activity change through the java code?

If you are just wanting to change the title bar, see this question ...

setTitle("My Title Is Better Than Your Title");