Java 如何获取对ListFragment'；来自MainActivity的适配器和基础数据？

我有一个用数据填充的ListFragment：

String list1 = {...arbitrary data...};
adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, list1);

但是接下来呢？对不起，我是Android的初学者

以下是我的主要活动：

public class MainActivity extends AppCompatActivity implements MyListFragment.Communicator, EditFragment.EditCallback{

    FragmentManager fragmentManager;
    FragmentTransaction fragmentTransaction;
    FragmentTransaction fragmentTransaction2;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        MyListFragment myListFragment = new MyListFragment();
        fragmentManager = getFragmentManager();
        fragmentTransaction = fragmentManager.beginTransaction();
        fragmentTransaction.add(R.id.fragContainer, myListFragment, "MyListFragment");
        fragmentTransaction.commit();
    }

    @Override
    public void onMyListItemClick(String name, int position) {
        EditFragment editFragment = new EditFragment();

        Bundle args = new Bundle();
        args.putString("name", name);
        args.putInt("position", position);
        editFragment.setArguments(args);

        fragmentTransaction2 = getFragmentManager().beginTransaction();
        fragmentTransaction2.replace(R.id.fragContainer, editFragment);
        fragmentTransaction2.addToBackStack(null);
        fragmentTransaction2.commit();
    }

    @Override
    public void updateItem(int position, String textUpdated) {
        //getting a reference to ListFragment:
        MyListFragment myListFragment = (MyListFragment) getFragmentManager().findFragmentByTag("MyListFragment");
        ArrayAdapter adapter = (ArrayAdapter) myListFragment.getListView().getAdapter();

    }
}

---

您可以在updateItem中更新后调用adapter.notifyDataSetChanged（），因为您已经获得了适配器。而且不需要创建任何新方法。以下是ArrayAdapter的链接，以了解更多信息

---

在MyListFragment中创建一个方法更新，并在MainActivity中调用它。更新可以更新你的列表。天哪，你真的救了我一天，谢谢@javastarter，您想从片段调用方法，并且您的方法处于活动状态，对吗？@HirenPatel，我需要通过接口通信从另一个片段访问ListFragment中的数据。正如Raghunandan建议的那样，我刚刚调用了myListFragment.changeItem，实际的实现保存在ListFragment中。谢谢！我不必实例化适配器，只需在ListFragment中调用实现的方法并在那里设置notifyDatasetChanged。

public class MainActivity extends AppCompatActivity implements MyListFragment.Communicator, EditFragment.EditCallback{

    FragmentManager fragmentManager;
    FragmentTransaction fragmentTransaction;
    FragmentTransaction fragmentTransaction2;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        MyListFragment myListFragment = new MyListFragment();
        fragmentManager = getFragmentManager();
        fragmentTransaction = fragmentManager.beginTransaction();
        fragmentTransaction.add(R.id.fragContainer, myListFragment, "MyListFragment");
        fragmentTransaction.commit();
    }

    @Override
    public void onMyListItemClick(String name, int position) {
        EditFragment editFragment = new EditFragment();

        Bundle args = new Bundle();
        args.putString("name", name);
        args.putInt("position", position);
        editFragment.setArguments(args);

        fragmentTransaction2 = getFragmentManager().beginTransaction();
        fragmentTransaction2.replace(R.id.fragContainer, editFragment);
        fragmentTransaction2.addToBackStack(null);
        fragmentTransaction2.commit();
    }

    @Override
    public void updateItem(int position, String textUpdated) {
        //getting a reference to ListFragment:
        MyListFragment myListFragment = (MyListFragment) getFragmentManager().findFragmentByTag("MyListFragment");
        ArrayAdapter adapter = (ArrayAdapter) myListFragment.getListView().getAdapter();

    }
}