Android控件之ExpandableListView

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ExpandableListView
android:id="@id/android:list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:drawSelectorOnTop="false">
</ExpandableListView>
<TextView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@id/android:empty"
android:text="No Data" />
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/child"
android:textSize="15sp"
android:paddingLeft="25px"
android:paddingTop="10px"
android:paddingRight="5px"
android:paddingBottom="10px"
android:text="No Data" />
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/group"
android:textSize="25sp"
android:paddingLeft="35px"
android:paddingTop="10px"
android:paddingRight="5px"
android:paddingBottom="10px"
android:text="No Data" />
</LinearLayout>

package com.zeph.android.expandablelistview.example;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.ExpandableListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ExpandableListView;
import android.widget.SimpleExpandableListAdapter;

public class ExpandableListViewActivity extends ExpandableListActivity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
List<Map<String, String>> groups = new ArrayList<Map<String, String>>();
// 创建两个一级条目标题
Map<String, String> group1 = new HashMap<String, String>();
group1.put("group", "音乐");
Map<String, String> group2 = new HashMap<String, String>();
group2.put("group", "歌词");
groups.add(group1);
groups.add(group2);
// 创建一级条目下的的二级条目
List<Map<String, String>> child1 = new ArrayList<Map<String, String>>();
// 同样是在一级条目目录下创建两个对应的二级条目目录
Map<String, String> childdata1 = new HashMap<String, String>();
childdata1.put("child", "青花瓷");
Map<String, String> childdata2 = new HashMap<String, String>();
childdata2.put("child", "东风破");
child1.add(childdata1);
child1.add(childdata2);
// 同上
List<Map<String, String>> child2 = new ArrayList<Map<String, String>>();
Map<String, String> childdata3 = new HashMap<String, String>();
childdata3.put("child", "青花瓷.lrc");
Map<String, String> childdata4 = new HashMap<String, String>();
childdata4.put("child", "东风破.lrc");
child2.add(childdata3);
child2.add(childdata4);
// 将二级条目放在一个集合里，供显示时使用
List<List<Map<String, String>>> childs = new ArrayList<List<Map<String, String>>>();
childs.add(child1);
childs.add(child2);
/**
* 使用SimpleExpandableListAdapter显示ExpandableListView 参数1.上下文对象Context
* 参数2.一级条目目录集合 参数3.一级条目对应的布局文件 参数4.fromto，就是map中的key，指定要显示的对象
* 参数5.与参数4对应，指定要显示在groups中的id 参数6.二级条目目录集合 参数7.二级条目对应的布局文件
* 参数8.fromto，就是map中的key，指定要显示的对象 参数9.与参数8对应，指定要显示在childs中的id
*/
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 });
setListAdapter(adapter);

}

/**
* 设置哪个二级目录被默认选中
*/
@Override
public boolean setSelectedChild(int groupPosition, int childPosition,
boolean shouldExpandGroup) {
// do something
return super.setSelectedChild(groupPosition, childPosition,
shouldExpandGroup);
}

/**
* 设置哪个一级目录被默认选中
*/
@Override
public void setSelectedGroup(int groupPosition) {
// do something
super.setSelectedGroup(groupPosition);
}

/**
* 当二级条目被点击时响应
*/
@Override
public boolean onChildClick(ExpandableListView parent, View v,
int groupPosition, int childPosition, long id) {
// do something
return super.onChildClick(parent, v, groupPosition, childPosition, id);
}

}