Question

I have a Fragment, which should execute a (public) Method reset() from the Activity in the Fragment it is called from.

I found, for example, this page:
Calling Activity methods from Fragment
The other way there’s no problem:

Input_tap Input_tap = (Input_tap) getFragmentManager().findFragmentById(R.id.input);
Input_tap.reset();

Does someone has any idea how to do it the other way?
and: Does the Method has to be public – its a “void” Method?

Answer 1

A Fragment can call getActivity() to retrieve the activity that is hosting it.

If there is only one possible activity that can host the fragment, just cast the Activity to the proper class (e.g., MyActivity) and call a method on it:

((MyActivity)getActivity()).someMethod();

If there might be more than one activity that can host the fragment, you are best served by implementing a common interface on all those activities, so you can cast getActivity()‘s result to that interface:

((MyInterface)getActivity()).someMethod();