Android Basic Learnings

I am learning Android and want to learn below points on Team Viewer. Ready to pay max 2$ for these Super Simple points.

1. emulator: emulator window was out of view and was re centred

2. How to do code indentation with keyboard short cut?

3. How to remove unnecessary references in file header ?

4. is there any way to remove unused functions and class scoped variable ?

5. Activity is derived from ActionBarActivity and there is strike through on this Class. Why ?

6. On change is not firing for Spinner.

安卓

项目ID： #7910194

关于项目