Difference between content_main.xml and activity_main.xml?

Question

I am new to Android App development. I have Android Studio 1.4. In my layout folder I have two XML files (content_main.xml and activity_main.xml).

Answer 1

The activity_main.xml is the "outer" part of the activity layout (toolbar, action button, etc.) and content_main.xml is the inner part where you put your own layout (the blank space).

content_main.xml file will be generated when you choose "blank activity". This activity will be having floating button by default at the bottom of the screen.

But when you choose "empty activity" then content_main.xml won't be generated and it won't be having floating button, but just simple Activity.