Need help how to access previous snippets for deletion?

Question

Android

There is a fragment that displays through the RecyclerView in the photo album, when you open the photo, another fragment opens. it has a delete button. I delete the photo on the server. but when you go back to the album by clicking the back button, the photo is in place until you restart the fragment.
I still don’t quite understand how to implement probably a listener in fragment1 and send a removal request from fragment2 to the first photo by ID from . close the fragment and so that this photo is not already in the list. tell me pzhsta how to implement it correctly, where to drip?

Answer 1

there are 2 approaches here:
1) simple:
using the life cycle of fragments, you can simply reload the list in the onResume callback
minus: the entire list will be reloaded
2) create the correct
interface implemented by the activity

interface OnRemoveItemListener{
   void removeItem(int pos);
}

public class ListFragment extends Fragment {
  ...
    public void itemRemoved(int pos){
    	adapter.getData().remove(pos);
    	adapter.notifyItemRemoved(pos);
    	//это все можно делать внутри адаптера, а здесь просто вызвать его метод
    }

}

public class DetailFragment extends Fragment {
  private OnRemoveItemListener listener;
  //позиция элемента в адаптере RecyclerView
  private int position;

  public static void newInstance(int pos){
    Bundle bundle = new Bundle();
    bundle.putInt("pos", pos);
    DetailFragment f = new DetailFragment();
    f.setArguments(bundle);
    return f;
  }

  @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        try {
            listener = (OnRemoveItemListener) context;
        } catch (ClassCastException e) {
            throw new ClassCastException(context.toString() + " must implement OnRemoveItemListener");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        listener = null;
    }

    public void onViewCreated(...){
    	//получаете pos из getArguments() и сохраняете в поле position
    }

//метод удаления на сервере
    public void removeItemFromApi(){
    	...
    	listener.removeItem(position);
    	...
    }

}

public class MainActivity extends AppCompatActivity implements OnRemoveItemListener{
  void removeItem(int pos){
    ListFragment f = (ListFragment)getSupportFragmentManager().findFragmentById(R.id.detailFragment);
    f.itemRemoved(pos);
  }
}