Android Development with Kotlin

Types of receivers

When we have a member extension function, then it becomes more complicated to administer the elements we are calling. Inside a member extension, we have implicit access to the following:

• Member functions and properties, both from this class and superclasses
• Receiver type functions and properties, both from the receiver type and its supertypes
• Top-level functions and properties

So inside the setUp extension function, we can use both member and receiver methods and properties:

 class MainActivity: Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.main_activity) val buttonView = findViewById(R.id.button_view) as Button buttonView.setUp() } private ...