Android Use Spaces for Indentation

We use 4 space indents for blocks. We never use tabs. When in doubt, be consistent with code around you.

We use 8 space indents for line wraps, including function calls and assignments. For example, this is correct:

Instrument i =
        someLongExpression(that, wouldNotFit, on, one, line);

and this is not correct:

Instrument i =
    someLongExpression(that, wouldNotFit, on, one, line);

Source: http://source.android.com/source/code-style.html