How should the

Stateful by state()

part of this should be interpreted?

class MySuperCoolActivity : Activity(), Stateful by state()

and

state()

is a global function

What is

Stateful

?

Stateful

is an interface, and

MySuperCoolActivity

implements that interface by delegating all calls to whatever

state()

returns.

Yes, `Stateful`is an interface, and

state()

is a function that returns an implementation of

state()

. The example I was looking at showed that you could then call functions of

Stateful

in your

MySuperCoolActivity

. Means you can offload implementation of interfaces to other classes while still keeping the ability to directly call the functions, neat!