Non-standard back button in Action Bar Android

Question

I've seen in several apps a non-standard back button (image #2) in the action bar,

Normally when I config a navigation drawer or the setDisplayHomeAsUpEnabled it just looks like image #1

How can i accomplish the non-standard style?

Answer 1

That is not a back button. It is sometimes called a "hamburger icon", and it is specifically used for indicating the presence of DrawerLayout navigation. You can find more information in the Android documentation. You can see more about the icon's functionality here.