关于安卓开发实现可展开的列表组件

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="fill_parent"
 4     android:layout_height="fill_parent"
 5     android:orientation="vertical" >
 6     <ExpandableListView 
 7         android:id="@id/android:list"
 8         android:layout_width="fill_parent"
 9         android:layout_height="fill_parent"
10         android:drawSelectorOnTop="false"
11                 />
12     <TextView 
13         android:layout_width="fill_parent"
14         android:layout_height="fill_parent"
15         android:id="@id/android:empty"
16         android:text="No Data"/> 
17 
18 </LinearLayout>

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="fill_parent"
 4     android:layout_height="fill_parent"
 5     android:orientation="vertical" >
 6     <TextView
 7         android:layout_width="fill_parent"
 8         android:layout_height="fill_parent"
 9         android:id="@+id/group"
10         android:textSize="25sp"
11         android:paddingLeft="35dp"
12         android:paddingRight="5dp"
13         android:paddingTop="10dp"
14         android:paddingBottom="10dp"
15         android:text="No Data"/>
16 
17 </LinearLayout>

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="fill_parent"
 4     android:layout_height="fill_parent"
 5     android:orientation="vertical" >
 6     <TextView
 7         android:layout_width="fill_parent"
 8         android:layout_height="fill_parent"
 9         android:id="@+id/child"
10         android:textSize="15sp"
11         android:paddingLeft="25dp"
12         android:paddingTop="10dp"
13         android:paddingRight="5dp"
14         android:paddingBottom="10dp"
15         android:text="No Data" 
16         />
17     
18 
19 </LinearLayout>

 1 package lianxi;
 2 
 3 import java.util.ArrayList;
 4 import java.util.HashMap;
 5 import java.util.List;
 6 import java.util.Map;
 7 
 8 import com.example.jichu_lianxi.R;
 9 
10 
11 import android.app.ExpandableListActivity;
12 import android.os.Bundle;
13 import android.view.View;
14 import android.widget.ExpandableListView;
15 import android.widget.SimpleExpandableListAdapter;
16 
17 public class List_lianxi extends ExpandableListActivity{            //继承ExpandableListActivity
18     @Override
19     public void onCreate(Bundle savedInstanceState) {
20         // TODO Auto-generated method stub
21         super.onCreate(savedInstanceState);
22         setContentView(R.layout.main);                               
23         
24         //创建一级条目容器
25         List<Map<String,String>>groups = new ArrayList<Map<String,String>>();
26         //创建两个一级条目标题
27         Map<String, String>group1 = new HashMap<String, String>();
28         group1.put("group", "音乐");
29         Map<String, String>group2 = new HashMap<String, String>();
30         group2.put("group", "歌词");
31         groups.add(group1);
32         groups.add(group2);
33         //创建一级条目下的二级条目
34         List<Map<String, String>> child_one = new  ArrayList<Map<String,String>>();
35         //在一级条目目录下创建两个对应的二级条目目录
36         Map<String, String> child_one_1 = new HashMap<String, String>();
37         child_one_1.put("child", "青花瓷");
38         Map<String, String> child_one_2 = new HashMap<String, String>();
39         child_one_2.put("child", "东风破");
40         child_one.add(child_one_1);
41         child_one.add(child_one_2);
42         
43         //第二个二级条目目录
44         List<Map<String, String>> child_two = new  ArrayList<Map<String,String>>();
45         Map<String, String> child_two_1 = new HashMap<String, String>();
46         child_two_1.put("child", "青花瓷.lrc");
47         Map<String, String> child_two_2 = new HashMap<String, String>();
48         child_two_2.put("child", "东风破.lrc");
49         child_two.add(child_two_1);
50         child_two.add(child_two_2);
51         
52         //将二级条目目录放在一个集合里供显示时使用
53         List<List<Map<String, String>>>childs = new ArrayList<List<Map<String,String>>>();
54         childs.add(child_one);
55         childs.add(child_two);
56         
57         /*
58          * 使用SimpleExpandableListAdapter显示ExpandableListView
59          * 参数1：上下文对象Context
60          * 参数2：一级条目目录集合
61          * 参数3：一级条目对应的布局文件
62          * 参数4：fromto,map中的key，指定要显示的对象
63          * 参数5：与参数4对应，指定要显示在groups中的id
64          * 参数6：二级条目目录集合
65          * 参数7：二级条目对应的布局文件
66          * 参数8：fromto.map中的key，指定要显示的对象
67          * 参数9：与参数8对应，指定要显示在childs中的id
68          */
69         SimpleExpandableListAdapter adapter = new SimpleExpandableListAdapter(this, groups, R.layout.groups, new String[]{"group"}, new int[]{R.id.group}, childs, R.layout.childs, new String[]{"child"}, new int[]{R.id.child});
70         setListAdapter(adapter);
71 
72     }
73     //设置哪个二级目录被默认选中
74     @Override
75     public boolean setSelectedChild(int groupPosition, int childPosition,
76             boolean shouldExpandGroup) {
77         // TODO Auto-generated method stub
78         return super.setSelectedChild(groupPosition, childPosition, shouldExpandGroup);
79     }
80     //设置哪个一级目录被默认选中
81     @Override
82     public void setSelectedGroup(int groupPosition) {
83         // TODO Auto-generated method stub
84         super.setSelectedGroup(groupPosition);
85     }//当二级条目被点击时响应
86     @Override
87     public boolean onChildClick(ExpandableListView parent, View v,
88             int groupPosition, int childPosition, long id) {
89         // TODO Auto-generated method stub
90         return super.onChildClick(parent, v, groupPosition, childPosition, id);
91     }
92 }