Could you please tell me difference between
Base Adapter as the name suggests, is a base class for all the adapters.
When you are extending the Base adapter class you need to implement all the methods like getcount,getid etc.
ArrayAdapter is a class which can work with array of data. you need to override only getview method
Listadapter is a an interface implemented by concrete adapter classes.
Base adapter is abstract class where as array adapter and the list adapter are the concrete classes.
Array adapter and listadapter classes are developed since in general we deal with the array data sets and list data sets.