Activity implements an interface (GreetingsInterface)
which exposes a method to spawn an instance of GreetingsFragment
that would show greetings.
First fragment would keep an instance of this interface
and would call showGreetings(name) method on it.
At this point, first fragment has delegated the task to implementer of interface i.e.,
Home activity in this case.
Now it’s up to Home how it handles it.