Fragment之间的数据互传

public class LeftFragment extends Fragment {
    String[] menus = new String[]{"Android", "IOS", "WP"};
    private OnClickItem onClickItem;


    public LeftFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view= inflater.inflate(R.layout.fragment_left, container, false);
        ListView lv= (ListView) view.findViewById(R.id.lv_menu);
        ArrayAdapter adapter=new ArrayAdapter(getActivity(),android.R.layout.simple_list_item_1,menus);
        lv.setAdapter(adapter);
       lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
           @Override
           public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//               MainActivity activity= (MainActivity) getActivity();
//               activity.setContent(menus[position]);
               if (onClickItem != null) {
                   onClickItem.setText(menus[position]);
               }
           }
       });
        return view;

    }
    //自定义接口
    public interface OnClickItem{
        void setText(String msg);
    }

public class RightFragment extends Fragment {
    private TextView tv_content;


    public RightFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view=inflater.inflate(R.layout.fragment_right, container, false);
        tv_content= (TextView) view.findViewById(R.id.tv_content);
        return view;
    }
    public void set_content(String msg){
        tv_content.setText(msg);
    }

public class MainActivity extends AppCompatActivity implements LeftFragment.OnClickItem{
    private RightFragment rfg;
    private LeftFragment lfg;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        rfg= (RightFragment) getSupportFragmentManager().findFragmentById(R.id.fr_right);
        lfg = (LeftFragment) getSupportFragmentManager().findFragmentById(R.id.fr_left);
        //初始化LeftFragment 调用LeftFragment的set方法

    }
//    public void setContent(String msg){
//        rfg.set_content(msg);
//    }

    @Override
    public void setText(String msg) {
        rfg.set_content(msg);
    }