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12,051 PointsWhy do we need to go back to the ListFragment class, get the activity and cast it onto the interface?
I didn't understand the reasoning behind anything past creating the interface and implementing it correctly in MainActivity.java. There wasn't much of an explanation either. What role does this part play in the process ?
1 Answer
Elias Caceres
8,454 PointsYou want to send a message to MainActivity from ListFragment.
You can't just do something like
MainActivity.doSomeMethod()
Instead, using an Interface is one way of creating a communication tunnel (one way) from Fragment to MainActivity. You cast the Interface with
getActivity()
because you need to specify which activity should recieve the message/callback.
Remember, this is only communication FROM Fragment TO MainActivity. If you want to communicate from MainActivity to Fragment, you will need to do something else, like use the FragmentManager.