Annotated Android Class Hierarchy

This diagram helped me: http://www.adakoda.com/adakoda/2010/01/20/ASPH_AW_REV1.pdf

And a little less useful, but with all the classes: http://troodon-software.com/archives/46

The hierarchy is not very deep. I think the best way to get acquainted might be to start with View and then look at the "direct subclasses" and "indirect subclasses" section at the top.

The big divisions for View are

• TextView - including EditText and Button
• ViewGroup - just about every container

Within ViewGroup there are both Layouts and more complicated widgets like the ListView family.

Try answering some questions on Stackoverflow, even if you are new. You'll have to learn all sorts of classes that you wouldn't have used otherwise.

Once you dive into writing code and learn to love the documentation, you'll naturally acquire a mental map of the classes.