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最新推荐文章于 2025-05-15 23:29:33 发布

原创最新推荐文章于 2025-05-15 23:29:33 发布 · 198 阅读

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本文介绍了一个使用Android支持库中的Fragment实现左右布局数据交互的案例。通过定义回调接口，LeftFragment负责展示列表并传递选中项数据给RightFragment，RightFragment接收数据并显示。

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//Fragment是静态注册

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;

public class MainActivity extends FragmentActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }

}

//Activity的布局界面

//LeftFragment界面

import java.util.ArrayList;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class LetfFragment extends Fragment {
   private View view;
   private ArrayList<String> list;

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

   @Override
   public void onActivityCreated(Bundle savedInstanceState) {
       super.onActivityCreated(savedInstanceState);
       ListView listView = (ListView) view.findViewById(R.id.listview);
       list = new ArrayList<String>();
       for (int i = 0; i < 20; i++) {
           list.add("这是第" + i + "条数据");
       }
       listView.setAdapter(new ArrayAdapter<String>(getActivity(),
               android.R.layout.simple_list_item_1, list));
       listView.setOnItemClickListener(new OnItemClickListener() {
           @Override
           public void onItemClick(AdapterView<?> parent, View view,
                   int position, long id) {
               String string = list.get(position);
               listener.onItemClick(string);
           }
       });

   }

   // 定义回调接口的步骤
   // 1. 定义一个接口OnListClickListener
   // 2.定义接口中的方法来将数据回传到需要接收数据的组件中onItemClick(String str)
   // 3.给外部提供一个设置回调接口的方法setListener（），参数就是回调接口的一个实例
   // 4.在需要回传数据的地方调用外部传来的接口实例的回调方法
   private OnListClickListener listener;

   public void setListener(OnListClickListener listener) {
       this.listener = listener;
   }

   interface OnListClickListener {
       void onItemClick(String str);
   }
}

//LeftFragment的布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
       <ListView
           android:id="@+id/listview"
       android:layout_width="match_parent"
           android:layout_height="match_parent" >
       </ListView>
</LinearLayout>

//RightFragment的页面

import com.bwie.fragmenttofragment.LetfFragment.OnListClickListener;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class RightFragment extends Fragment {
   private View view;
   private TextView textView;
   @Override
   public View onCreateView(LayoutInflater inflater, ViewGroup container,
           Bundle savedInstanceState) {
       view = inflater.inflate(R.layout.activity_fragment_right, container,false);
       return view;
   }
   @Override
   public void onActivityCreated(Bundle savedInstanceState) {
       super.onActivityCreated(savedInstanceState);
       textView = (TextView) view.findViewById(R.id.textview);
       LetfFragment letfFragment = (LetfFragment) getActivity().getSupportFragmentManager().findFragmentById(R.id.fragment_left);
       // 外部在需要设置回调接口的地方，设置回调接口的实例，然后在接口的回调方法中接收传回来的数据
       letfFragment.setListener(new OnListClickListener() {

           @Override
           public void onItemClick(String str) {
               textView.setText(str);
           }
       });
   }

}

//RightFragment的布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
   <TextView
          android:id="@+id/textview"
        android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:gravity="center" />
</LinearLayout>