ExpandableListView的简单案例

ExpandableListView介绍：

 长话短说，ExpandableListView就是ListView的扩展。像QQ好友分组列表。看下面的效果图，就知道了。

效果图:

 

ExpandableListView有几个属性值得一说：

android:childDivider

来分离子列表项的图片或者是颜色。注：图片不会完全显示，分离子列表项的是一条直线

android:childIndicator

在子列表项旁边显示的指示符。注：可以是一个图片

android:childIndicatorLeft

子列表项指示符的左边约束位置。注：即从左端0位置开始计数，比如，假设指示符是一个图标，给定这个属性值为3dip，则表示从左端起3dip开始显示此图标。

android:childIndicatorRight

子列表项指示符的右边约束位置。注：表示右端到什么位置结束

android:groupIndicator

在组列表项旁边显示的指示符。注：可以是一个图片，如果不想要指示器可以设置为@null。

android:indicatorLeft

组列表项指示器的左边约束位置。注：表示左端从什么位置开始（测试了下，在android 4.4的模拟器下没效果）。

android:indicatorRight

组列表项指示器的右边约束位置。注：表示右端到什么位置结束（测试了下，在android 4.4的模拟器下没效果）。

代码：

package cn.datian.expandablelistviewtest2;

import java.util.ArrayList;
import java.util.List;

import android.os.Bundle;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;
import android.widget.Toast;

@SuppressLint("NewApi")
public class MainActivity extends Activity {

    /**
     * 子类的数据集合
     */
    private List<List<String>> childrenList;
    /**
     * 组集合
     */
    private List<String> groupList;
    
    private ExpandableListView eListView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initDate();
        eListView = (ExpandableListView) this.findViewById(R.id.eListView);
        eListView.setAdapter(adapter);
        //展开第一组,调用了expandGroup(4,false);
        eListView.expandGroup(0);
        //下标从0开始，展开第五组，为true表示滚动到第五组的位置。
//        eListView.expandGroup(4,true);
        
        eListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
            
            @Override
            public boolean onGroupClick(ExpandableListView parent, View v,
                    int groupPosition, long id) {
                Toast.makeText(MainActivity.this, "你点击了："+groupList.get(groupPosition),Toast.LENGTH_SHORT).show();
                return false;
            }
        });
        
        //点击组下的子条目监听
        eListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
            
            @Override
            public boolean onChildClick(ExpandableListView parent, View v,
                    int groupPosition, int childPosition, long id) {
                Toast.makeText(MainActivity.this, "你点击了："+childrenList.get(groupPosition).get(childPosition), Toast.LENGTH_SHORT).show();
                return true;
            }
        });
    }

    /**
     * 初始化数据
     */
    private void initDate() {
        
        childrenList = new ArrayList<List<String>>();
        groupList = new ArrayList<String>();
        
        addDate("小学","张三");
        addDate("中学","李四");
        addDate("高中","王五");
        addDate("大学","赵六");
        addDate("硕士","小红");
        addDate("博士","小明");
        addDate("博士后","大明");
        
    }

    private void addDate(String group, String chlidren) {
        
        groupList.add(group);
        List<String> cs = new ArrayList<String>();
        for(int i = 0;i < 10;i++){
            cs.add(chlidren+i);
        }
        childrenList.add(cs);
    }
    
    
    
    BaseExpandableListAdapter adapter = new BaseExpandableListAdapter() {
        
        
        /**
         * 返回true,表明子条目是可选的。
         */
        @Override
        public boolean isChildSelectable(int groupPosition, int childPosition) {
            Log.i("adpter", "isChildSelectable");
            return true;
        }
        
        @Override
        public boolean hasStableIds() {
            Log.i("adpter", "hasStableIds");
            return false;
        }
        
        @Override
        public View getGroupView(int groupPosition, boolean isExpanded,
                View convertView, ViewGroup parent) {
            
            Log.i("adpter", "getGroupView");
            View v = View.inflate(MainActivity.this, R.layout.group_item,null);
            
            TextView tv=  (TextView) v.findViewById(R.id.tv);
            tv.setText(groupList.get(groupPosition));
            tv.setPadding(20, 0, 0, 0);
            return v;
        }
        
        @Override
        public long getGroupId(int groupPosition) {
            Log.i("adpter", "getGroupId");
            return groupPosition;
        }
        
        @Override
        public int getGroupCount() {
            Log.i("adpter", "getGroupCount");
            return groupList.size();
        }
        
        @Override
        public Object getGroup(int groupPosition) {
            Log.i("adpter", "getGroup");
            return groupList.get(groupPosition);
        }
        
        @Override
        public int getChildrenCount(int groupPosition) {
            Log.i("adpter", "getChildrenCount");
            return childrenList.get(groupPosition).size();
        }
        
        @Override
        public View getChildView(int groupPosition, int childPosition,
                boolean isLastChild, View convertView, ViewGroup parent) {
            Log.i("adpter", "getChildView");
            TextView tv = new TextView(MainActivity.this);
            tv.setText(childrenList.get(groupPosition).get(childPosition));
            tv.setPadding(20, 0, 0, 0);
            return tv;
        }
        
        @Override
        public long getChildId(int groupPosition, int childPosition) {
            Log.i("adpter", "getChildId");
            return childrenList.get(groupPosition).size();
        }
        
        @Override
        public Object getChild(int groupPosition, int childPosition) {
            Log.i("adpter", "getChild");
            return childrenList.get(groupPosition).get(childPosition);
        }
    };
}

 layout布局:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
     >

    <ExpandableListView 
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/eListView"
        android:groupIndicator="@drawable/expandable_indicator_selector"
        android:indicatorLeft="5dp"
        android:indicatorRight="30dp"
        ></ExpandableListView>
</RelativeLayout>

 layout组条目布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" 
    android:layout_margin="10dp"
    >
    <TextView 
        android:id="@+id/tv"
        android:layout_width="wrap_content"
        android:layout_height="50dp"
        android:text=""
        android:textSize="20sp"
        android:layout_marginLeft="40dp"
        android:gravity="center_vertical"
        />
</LinearLayout>

android:groupIndicator="@drawable/expandable_indicator_selector" ： 使用选择器

选择器代码：

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:state_expanded="true" android:drawable="@drawable/contract" />   
    <item android:drawable="@drawable/expand"></item> 
</selector>