Question

Looking at various pages in the Android docs, some of them list “Known Indirect Subclasses”. What does this mean?

Answer 1

For an interface, it’s a list of classes that implement the interface.

For a class, it’s a list of classes that derive from the class, but indirectly (ie., the class in the list is derived from some class that itself derives from the class being documented directly or indirectly).

So the android.view.ViewGroup derives directly from android.view.View and indirectly from java.lang.Object:

java.lang.Object
    android.view.View
        android.view.ViewGroup

Since interfaces can only be implemented, not directly derived from, a class that implements an interface is always considered to be ‘indirectly derived’ from the interface.