ExpandableListView是android中可以实现下拉list的一个控件，是一个垂直滚动的心事两个级别列表项手风琴试图，列表项是来自ExpandableListViewaAdapter，组可以单独展开。
重要方法：
expandGroup (int groupPos) ;//在分组列表视图中 展开一组，
setSelectedGroup (int groupPosition) ;//设置选择指定的组。
setSelectedChild (int groupPosition, int childPosition, boolean shouldExpandGroup);//设置选择指定的子项。
getPackedPositionGroup (long packedPosition);//返回所选择的组
getPackedPositionForChild (int groupPosition, int childPosition) ;//返回所选择的子项
getPackedPositionType (long packedPosition);//返回所选择项的类型（Child,Group）
isGroupExpanded (int groupPosition);//判断此组是否展开
expandableListView.setDivider();这个是设定每个Group之间的分割线。
expandableListView.setGroupIndicator();这个是设定每个Group之前的那个图标。
expandableListView.collapseGroup(int group); 将第group组收起
ExpandableListAdapter
一个接口，将基础数据链接到一个ExpandableListView。 此接口的实施将提供访问Child的数据（由组分类），并实例化的Child和Group。
1.重要方法
getChildId (int groupPosition, int childPosition) 获取与在给定组给予孩子相关的数据。
getChildrenCount (int groupPosition) 返回在指定Group的Child数目。
案例：
首先定义个一个布局文件expandablelistview.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ExpandableListView
android:id ="@+id/expandableListView"
android:layout_width ="fill_parent"
android:layout_height ="wrap_content"
>
</ExpandableListView>
</LinearLayout>
package com.test;
import java.util.ArrayList;
import java.util.List;
import javax.security.auth.PrivateCredentialPermission;
import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;
public class ExpandableListViewDemo extends Activity {
/** Called when the activity is first created. */
//定义两个List用来控制Group和Child中的String;
private List<String> groupArray;//组列表
private List<List<String>> childArray;//子列表
private ExpandableListView expandableListView_one;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// requestWindowFeature(Window.FEATURE_NO_TITLE); //设置为无标题
setContentView(R.layout.expandablelistview);
expandableListView_one =(ExpandableListView)findViewById(R.id.expandableListView);
groupArray =new ArrayList<String>();
childArray = new ArrayList<List<String>>();
/*-第一季-*/
initdate();
expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));
/*-第二季-*/
// groupArray.add("移动开发");
// List<String> arrayList = new ArrayList<String>();
// arrayList.add("Android");
// arrayList.add("IOS");
// arrayList.add("Windows Phone");
// //组循环
// for(int index=0;index<groupArray.size();++index)
// {
// childArray.add(arrayList);
// }
// expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));
}
class ExpandableListViewaAdapter extends BaseExpandableListAdapter {
Activity activity;
public ExpandableListViewaAdapter(Activity a)
{
activity = a;
}
/*-----------------Child */
@Override
public Object getChild(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return childArray.get(groupPosition).get(childPosition);
}
@Override
public long getChildId(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return childPosition;
}
@Override
public View getChildView(int groupPosition, int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
String string =childArray.get(groupPosition).get(childPosition);
return getGenericView(string);
}
@Override
public int getChildrenCount(int groupPosition) {
// TODO Auto-generated method stub
return childArray.get(groupPosition).size();
}
/* ----------------------------Group */
@Override
public Object getGroup(int groupPosition) {
// TODO Auto-generated method stub
return getGroup(groupPosition);
}
@Override
public int getGroupCount() {
// TODO Auto-generated method stub
return groupArray.size();
}
@Override
public long getGroupId(int groupPosition) {
// TODO Auto-generated method stub
return groupPosition;
}
@Override
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
String string=groupArray.get(groupPosition);
return getGenericView(string);
}
@Override
public boolean hasStableIds() {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition)
{
// TODO Auto-generated method stub
return true;
}
private TextView getGenericView(String string )
{
AbsListView.LayoutParams layoutParams =new AbsListView.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
TextView textView =new TextView(activity);
textView.setLayoutParams(layoutParams);
textView.setGravity(Gravity.CENTER_VERTICAL |Gravity.LEFT);
textView.setPadding(40, 0, 0, 0);
textView.setText(string);
return textView;
}
}
private void initdate()
{
addInfo("语言", new String[]{"Oracle","Java","Linux","Jquery"});
addInfo("男人的需求", new String[]{"金钱","事业","权力","女人","房子","车","球"});
}
private void addInfo(String group,String []child) {
groupArray.add(group);
List<String> childItem =new ArrayList<String>();
for(int index=0;index<child.length;index++)
{
childItem.add(child[index]);
}
childArray.add(childItem);
}
}
运行效果：
注释修改如下代码：
/*-第一季-*/
// initdate();
// expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));
/*-第二季-*/
groupArray.add("移动开发");
List<String> arrayList = new ArrayList<String>();
arrayList.add("Android");
arrayList.add("IOS");
arrayList.add("Windows Phone");
//组循环
for(int index=0;index<groupArray.size();++index)
{
childArray.add(arrayList);
}
expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));
运行效果：
★★★★★★★★★★★★★★★★★★★★
案例二：
1.定义一个主界面expandablelistview.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ExpandableListView
android:id ="@+id/expandableListView"
android:layout_width ="fill_parent"
android:layout_height ="wrap_content"
>
</ExpandableListView>
</LinearLayout>
2.在res/drawable目录下创建样式文件expandablelistview_groups.xml该界面是组界面：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textGroup"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingLeft="40px"
android:paddingTop="6px"
android:paddingBottom="6px"
android:textSize="15sp"
android:text="No data"
>
</TextView>
</LinearLayout>
3.在res/drawable目录下创建样式文件expandablelistview_child.xml；是子控件，直接显示列表内容
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textChild"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingLeft="60px"
android:paddingTop="10px"
android:paddingBottom="10px"
android:textSize="20sp"
android:text="No Data" />
</LinearLayout>
定义java文件：ExpandableListViewDemo_two.java
package com.test;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.security.auth.PrivateCredentialPermission;
import com.test.R;
import com.test.ExpandableListViewDemo.ExpandableListViewaAdapter;
import com.test.R.id;
import com.test.R.layout;
import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.SimpleExpandableListAdapter;
import android.widget.TextView;
public class ExpandableListViewDemo_two extends Activity {
/** Called when the activity is first created. */
private ExpandableListView expandableListView_one;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.expandablelistview);
expandableListView_one =(ExpandableListView)findViewById(R.id.expandableListView);
//创建二个一级条目标题
Map<String, String> title_1 = new HashMap<String, String>();
Map<String, String> title_2 = new HashMap<String, String>();
title_1.put("group", "移动开发");
title_2.put("group", "男人的需求");
//创建一级条目容器
List<Map<String, String>> gruops = new ArrayList<Map<String,String>>();
gruops.add(title_1);
gruops.add(title_2);
//创建二级条目内容
//内容一
Map<String, String> content_1 = new HashMap<String, String>();
Map<String, String> content_2 = new HashMap<String, String>();
content_1.put("child", "ANDROID");
content_2.put("child", "IOS");
List<Map<String, String>> childs_1 = new ArrayList<Map<String,String>>();
childs_1.add(content_1);
childs_1.add(content_2);
//内容二
Map<String, String> content_3 = new HashMap<String, String>();
Map<String, String> content_4 = new HashMap<String, String>();
Map<String, String> content_5 = new HashMap<String, String>();
content_3.put("child", "金钱");
content_4.put("child", "权力");
content_5.put("child", "女人");
List<Map<String, String>> childs_2 = new ArrayList<Map<String,String>>();
childs_2.add(content_3);
childs_2.add(content_4);
childs_2.add(content_5);
//存放两个内容, 以便显示在列表中
List<List<Map<String, String>>> childs = new ArrayList<List<Map<String,String>>>();
childs.add(childs_1);
childs.add(childs_2);
//创建ExpandableList的Adapter容器
/**
* 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 （expandablelistview_groups.xml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9.与参数8对应，指定要显示在childs中的id
/ SimpleExpandableListAdapter adapter = new SimpleExpandableListAdapter(
this, gruops, R.drawable.expandablelistview_groups, new String[]{"group"}, new int[]{R.id.textGroup},
childs, R.drawable.expandablelistview_child, new String[]{"child"}, new int[]{R.id.textChild}
);
//加入列表
expandableListView_one.setAdapter(adapter);
expandableListView_one.setOnChildClickListener(listener);
}
private OnChildClickListener listener =new OnChildClickListener() {
@Override
public boolean onChildClick(ExpandableListView parent, View v,
int groupPosition, int childPosition, long id) {
// TODO Auto-generated method stub
toast("点击了");
return false;
}
};
private void toast(String str) {
Toast.makeText(this, str, Toast.LENGTH_LONG).show();
}
}
上面的样式也可以使用系统的自带的样式如下：
android.R.layout.simple_expandable_list_item_1,//层显示样式 ，系统自定义
android.R.layout.simple_expandable_list_item_2,
运行效果：
案例三：如果group中有个ImageVIew将会是什么情况呢？
在SimpleExpandableListAdapter中有如下方法：
private void bindView(View view, Map<String, ?> data, String[] from, int[] to) {
int len = to.length;
for (int i = 0; i < len; i++) {
TextView v = (TextView)view.findViewById(to[i]);
if (v != null) {
v.setText((String)data.get(from[i]));
}
}
}
从上面的方法中可以看出 SimpleExpandableListAdapter把所以的View都当成TextView来处理了，而不像SimpleAdapter可以自动判断View的类型,自动绑定，解决版本就是重写bingview回调一下试试：
public class MyExpandableListAdapter extends BaseExpandableListAdapter{
private void bindView(View view, Map<String, ?> data, String[] from, int[] to) {
int len = to.length;
boolean isBound = false;
for (int i = 0; i < len; i++) {
final View v = view.findViewById(to[i]);
if (v!=null) {
final Object _data = data.get(from[i]);
String text = _data == null ? "" : data.toString();
if (text == null) {
text = "";
}
if (mViewBinder != null) {//如果Binder不为空,使用Binder进行处理
isBound = mViewBinder.setViewValue(v, data.get(from[i]), text);
}
if (!isBound) {//如果Binder跳过,使用原来的方法进行处理
TextView _v = (TextView)v;
_v.setText((String)data.get(from[i]));
}
}
}
}
}
