java - 在android中将数据从一个 fragment 传递到下一个 fragment

Question

在我的一个项目中，我使用 2 个 fragment 。一个 fragment 显示项目列表。所以我希望当在第一个 fragment 中选择主题时，应在另一个 fragment 中更改详细信息。我能够传递的数据从一个 fragment 到另一个 fragment ，但 View 没有改变。我应该在哪种方法中实现第二个 fragment 的 View ，以便它可以相应地改变。请给我很好的教程或示例。

在这里我必须开发一个android示例，我必须运行应用程序意味着在我的第一个 fragment 的水平 ListView 上很好地显示类别名称。我必须单击任何类别意味着我如何在第二个 fragment 上传递类别名称。请给我这个问题的解决方案。

我使用了以下代码:

public class Home extends FragmentActivity{

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
}

第一个 fragment 代码:

public class MainActivity extends Fragment {
static final String URL = "http://dev2.mercuryminds.com/webservices/new_feed_articls.xml";

 static String KEY_CATEGORY = "Categories";

 static final String KEY_TITLE = "Category";
 LazyAdapter adapter;

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


    final ArrayList<HashMap<String, String>> songsList = new ArrayList<HashMap<String, String>>();
    XMLParser parser = new XMLParser();
        String xml = parser.getXmlFromUrl(URL); // getting XML from URL
        Document doc = parser.getDomElement(xml); // getting DOM element

        NodeList nl = doc.getElementsByTagName(KEY_TITLE);


        // looping through all song nodes &lt;song&gt;
        for (int i = 0; i < nl.getLength(); i++) {
            // creating new HashMap
            HashMap<String, String> map = new HashMap<String, String>   ();
            Element e = (Element) nl.item(i);
            map.put( KEY_TITLE,((Element)nl.item(i)).getAttribute("name"));

           // map.put(KEY_TITLE, parser.getValue(e, KEY_TITLE));
            songsList.add(map);
        }
        HorizontalListView list = (HorizontalListView) view.findViewById(R.id.listView1);
    adapter = new LazyAdapter(getActivity(), songsList);
      list.setAdapter(adapter);

       list.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {
            HashMap<String, String> map = songsList.get(position);
            Intent in = new Intent();
            in.setClass(getActivity(), SubCate.class);
           // in.putExtra(KEY_TITLE, map.get(KEY_TITLE));

                     startActivity(in); 
        }  

     });
        return view;
    }}

我如何在第二个 Activity 上显示类别名称...请给我这些代码...

编辑:

嗨，我已经更改了代码，就像我的第一个 Activity 一样:

   HashMap<String, String> map = songsList.get(position);
            SubCate frag = (SubCate) getFragmentManager().findFragmentById(R.id.frag_2);
            if (frag != null && frag.isInLayout()) {
            frag.setText(getCapt(map));
            }
            }
            private String getCapt(HashMap<String, String> map) {
            if (map.containsValue("notchbolly")) {
            return "dadad";
            }
                return "veeman"; 

下一个 Activity :

public void setText(String item) {
 TextView view = (TextView) getView().findViewById(R.id.cate);
 view.setText(item);
  }

它醒得很好，同时直接在 if (map.containsValue("notchbolly")) 上提及名称。但是我必须显示名称而不直接提及名称。如果我必须单击任何类别意味着类别名称显示在下一个 fragment 。我该怎么办??????

Answer 1

使用接口(interface)方法我们可以在 fragment 之间传输数据

在fragmentA中创建接口(interface)并向该接口(interface)发送数据，并在fragmentB中实现该接口(interface)方法并获取所需数据

下面的代码对你有用

FragmentA 中的代码:

    public class FragmentA extends Fragment  {

    // interface method
    public    InterfaceDataCommunicatorBetweenfragmentAToFragmentB     iInterfaceDataCommunicatorBetweenfragmentAToFragmentB;

    // Data to send
    String mDataString;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        // use this line where u send data  
        iInterfaceDataCommunicatorBetweenfragmentAToFragmentB.upDatedData(mDataString);

        View view = inflater.inflate(R.layout.sent_box, container, false);


        return view ;
    }

    /**
         * Interface method to send data to fragmentB
         * 
         */
        public interface InterfaceDataCommunicatorBetweenfragmentAToFragmentB                                       {
            public void upDatedData(String data);

        }
    }

FragmentB 中的代码:

   class FragmentB extends Fragment implements InterfaceDataCommunicatorBetweenfragmentAToFragmentB {

    // interface method
    public InterfaceDataCommunicatorBetweenfragmentAToFragmentB iInterfaceDataCommunicatorBetweenfragmentAToFragmentB;

    // fragmentA data
    String mgetUpdatedData


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {


            View view = inflater.inflate(R.layout.get_box, container, false);


        return view ;
    }

   /**
     * Interface method coming from fragment a to fragmentB after  implement interface in fragmentB
     */
    public void upDatedData(String data) {
        this.mgetUpdatedData = data;
    }

    @Override
    public void onAttach(Activity activity) {
        // TODO Auto-generated method stub
        super.onAttach(activity);
        try {
            iInterfaceDataCommunicatorBetweenfragmentAToFragmentB = (InterfaceDataCommunicatorBetweenfragmentAToFragmentB ) activity;
        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString()
                    + " must implement interface");
        }

    }