When you want to use class Bar from package foo,there are two possible ways to import it:
import foo.*;
Pros: Potentially reduces the number of import statements.
import foo.Bar;
Pros: Makes it obvious what classes are actually used. Makes code more readable for maintainers.
Decision: Use the latter for importing all Android code. An explicit exception is made for java standard libraries (java.util.*, java.io.*, etc.) and unit test code (junit.framework.*)