Android Communication between two Fragments

FirstFragment.java

public class FirstFragment extends Fragment {

    Button buttonSend;
    EditText editTextName;

    private OnFragment1InteractionListener mListener;

    public FirstFragment() {

    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view= inflater.inflate(R.layout.fragment_first, container, false);

        buttonSend= (Button) view.findViewById(R.id.buttonSend);
        editTextName= (EditText) view.findViewById(R.id.editTextName);

        buttonSend.setOnClickListener(onClickListener);

        return view;
    }

    View.OnClickListener onClickListener=new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String name=editTextName.getText().toString();
            onButtonPressed(name);
        }
    };

    public void onButtonPressed(String name) {
        if (mListener != null) {
            mListener.onFragment1ButtonClicked(name);
        }
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof OnFragment1InteractionListener) {
            mListener = (OnFragment1InteractionListener) context;
        } else {
            throw new RuntimeException(context.toString()
                    + " must implement OnFragment1InteractionListener");
        }
    }

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

    public interface OnFragment1InteractionListener {
        void onFragment1ButtonClicked(String name);
    }
}

SecondFragment.java

public class SecondFragment extends Fragment {

    TextView textViewMessage;

    public SecondFragment() {

    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View  view= inflater.inflate(R.layout.fragment_second, container, false);

        textViewMessage= (TextView) view.findViewById(R.id.textViewMessage);

        return view;
    }

    public void setTextViewMessage(String name)
    {
        textViewMessage.setText("Hello " + name);
    }
}

MainActivity.java

public class MainActivity extends AppCompatActivity implements FirstFragment.OnFragment1InteractionListener{

    RelativeLayout container1;
    RelativeLayout container2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        container1= (RelativeLayout) findViewById(R.id.relativeLayoutContainer1);
        container2= (RelativeLayout) findViewById(R.id.relativeLayoutContainer2);

        FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();


        FirstFragment firstFragment=new FirstFragment();
        SecondFragment secondFragment=new SecondFragment();

        transaction.add(R.id.relativeLayoutContainer1,firstFragment);
        transaction.add(R.id.relativeLayoutContainer2,secondFragment);

        transaction.commit();
    }

    @Override
    public void onFragment1ButtonClicked(String name) {
        SecondFragment fragment= (SecondFragment) getSupportFragmentManager().findFragmentById(R.id.relativeLayoutContainer2);
        fragment.setTextViewMessage(name);
    }
}

References
https://github.com/mhdr/AndroidSamples/tree/master/032

Related