ExpandableListView的简单例子

最近一段时间参考网上的例子，做了一下简单的 ExpandableListView，现在和大家共享一下：

1：main.xml的内容

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout   
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/linearLayout"  
     android:layout_width="fill_parent"   
     android:layout_height="fill_parent"  
     androidrientation="vertical"  
     >  
       
     <ExpandableListView  
     android:id="@+id/expandableListView"  
     android:layout_width="fill_parent"  
     android:layout_height="wrap_content"  
         />  
</LinearLayout>

显示一个ExpandableListView

2：ExpandableListViewDemo 类的内容

package com.chama.expandablelistviewdemo;

import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;

public class ExpandableListViewDemo extends Activity {
    
     //定义两个List，用来存放控件中Group/Child中的String
    private List<String> groupArray;        
    private List<List<String>> childArray;
    
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        //对这两个List进行初始化，并插入一些数据
         groupArray = new ArrayList<String>();  
         childArray = new ArrayList<List<String>>();  
          
         groupArray.add("第一行");  
         groupArray.add("第二行");  
           
         List<String> tempArray = new ArrayList<String>();  
         tempArray.add("第一条");  
         tempArray.add("第二条");  
         tempArray.add("第三条");  
          
        for(int index = 0; index <groupArray.size(); ++index)  
        {  
           childArray.add(tempArray);  
       }  
        
       //给定义好的ExpandableListView添加上Adapter
       ExpandableListView expandableListView = (ExpandableListView)findViewById(R.id.expandableListView);
       ExpandableAdapter adapter = new ExpandableAdapter(this);
       expandableListView.setAdapter(adapter);
       
    }
    
    //定义ExpandableListView的Adapter
     public class ExpandableAdapter extends BaseExpandableListAdapter  
     {  
         Activity activity;  
           
         public ExpandableAdapter(Activity a)  
         {  
             activity = a;  
         }  
         
         public Object getChild(int groupPosition, int childPosition)  
         {  
             return childArray.get(groupPosition).get(childPosition);  
         } 
         
         public long getChildId(int groupPosition, int childPosition)  
         {  
             return childPosition;  
         } 
         
         public int getChildrenCount(int groupPosition)  
         {  
             return childArray.get(groupPosition).size();  
         } 
         
         public View getChildView(int groupPosition, int childPosition,  
                 boolean isLastChild, View convertView, ViewGroup parent)  
         {  
             String string = childArray.get(groupPosition).get(childPosition);  
             return getGenericView(string);  
         }  
         
         // group method stub  
         public Object getGroup(int groupPosition)  
         {  
             return groupArray.get(groupPosition);  
         }  
         
         public int getGroupCount()  
         {  
             return groupArray.size();  
         } 
         
         public long getGroupId(int groupPosition)  
         {  
             return groupPosition;  
         }  
         
         public View getGroupView(int groupPosition, boolean isExpanded,  
                 View convertView, ViewGroup parent)  
         {  
             String string = groupArray.get(groupPosition);  
             return getGenericView(string);  
         }  
         
         // View stub to create Group/Children 's View  
         public TextView getGenericView(String string)  
         {  
             // Layout parameters for the ExpandableListView  
             AbsListView.LayoutParams layoutParams = new AbsListView.LayoutParams(  
                     ViewGroup.LayoutParams.FILL_PARENT, 64);  
             TextView text = new TextView(activity);  
             text.setLayoutParams(layoutParams);  
             // Center the text vertically  
             text.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);  
             // Set the text starting position  
             text.setPadding(36, 0, 0, 0);  
             text.setText(string);  
             return text;  
         }  
         
        public boolean hasStableIds()  
         {  
             return false;  
         }  
         public boolean isChildSelectable(int groupPosition, int childPosition)  
         {  
             return true;  
         }  
     }  
}

需要注意的内容：

  1：groupArray 和childArray的内容，分别定义父对象和子对象显示的内容

  2：ExpandableAdapter继承了BaseExpandableListAdapter，并重载了其中的一些方法， 注意public TextView getGenericView(String string)的作用，主要用形成显示父对象和子对象视图的类

3：程序效果