Android custom round button

Question

I want to have a Button/ImageButton that looks like this (round button on the left)

What are my choices? Can I draw it using a shape? or is it better to use a png icon for that? ideas? What I want to do is to be able to display a new activity when the button is clicked/touched.

Answer 1

It is

android.R.drawable.expander_ic_minimized

look into built in android drawables:

http://androiddrawableexplorer.appspot.com/