效果图如下：
二级列表附有点击事件。
1、布局文件：
此处加了一个自定义的导航RelativeLayout，记得注activity的时候添加 android:theme="@style/Theme.AppCompat.Light.NoActionBar" 去掉自带的导航。
<?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"> <RelativeLayout
android:layout_width="match_parent"
android:layout_height="@dimen/dimen_55"
android:background="@color/main_title"
>
<TextView
android:layout_centerVertical="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="取消"
android:textColor="@color/white"
android:textSize="@dimen/dimen_18"
android:layout_marginLeft="@dimen/dimen_13"
android:onClick="goBack"
/>
<TextView
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="安卓二级列表"
android:textColor="@color/white"
android:textSize="@dimen/dimen_18"/>
</RelativeLayout> <!--二级菜单-->
<ExpandableListView
android:id="@+id/expandableListView"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</ExpandableListView> </LinearLayout>
2、一级列表布局：
ImageView是用来自定义打开闭合图标的（不自定义也可以，箭头会默认在最左边），建议自己用一个ImageView控件来控制上下箭头。图标可以去阿里巴巴矢量图上下载。
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal" android:layout_width="match_parent"
android:layout_height="wrap_content">
<!--一级列表 item布局--> <RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="@+id/tv_group"
android:layout_width="wrap_content"
android:layout_height="30dp"
android:gravity="center"
android:text="group text"
/>
<ImageView
android:id="@+id/iv_group"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:layout_marginRight="@dimen/dimen_20"
android:layout_width="20dp"
android:layout_height="20dp" />
</RelativeLayout> </LinearLayout>
3、二级列表布局：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal" android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center">
<!--二级列表 item布局--> <ImageView
android:id="@+id/iv_child"
android:layout_width="30dp"
android:layout_height="30dp"
android:src="@mipmap/ic_launcher" />
<TextView
android:id="@+id/tv_child"
android:layout_marginLeft="@dimen/dimen_20"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="item text" /> </LinearLayout>
4、activity代码：
private ExpandableListView expandableListView;
//一级列表数据源
private String[] groups = {"软件设计", "数据库技术", "操作系统"};
//二级列表数据源
private String[][] childs={{"架构设计","面向对象","设计模式","领域驱动设计"},{"SQL Server","Oracle","MySql", "Dameng "},{"Linux","Windows","嵌入式"}};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_expandable_listview);
initView();
}
private void initView() {
expandableListView = (ExpandableListView)findViewById(R.id.expandableListView);
//#TODO 去掉自带箭头，在一级列表中动态添加
expandableListView.setGroupIndicator(null);
expandableListView.setAdapter(new MyExpandableListView());
}
public void goBack(View view) {
finish();
}
5、ExpandableListView适配器：
继承自BaseExpandableListAdapter，重写ExpandableListAdapter中的10个方法
class MyExpandableListView extends BaseExpandableListAdapter {
/*一级列表个数*/
@Override
public int getGroupCount() {
return groups.length;
}
/*每个二级列表的个数*/
@Override
public int getChildrenCount(int groupPosition) {
return childs[groupPosition].length;
}
/*一级列表中单个item*/
@Override
public Object getGroup(int groupPosition) {
return groups[groupPosition];
}
/*二级列表中单个item*/
@Override
public Object getChild(int groupPosition, int childPosition) {
return childs[groupPosition][childPosition];
}
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
/*每个item的id是否固定，一般为true*/
@Override
public boolean hasStableIds() {
return true;
}
/*#TODO 填充一级列表
* isExpanded 是否已经展开
* */
@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
if (convertView == null) {
convertView = getLayoutInflater().inflate(R.layout.list_item_expandablelistview,null);
}
TextView tv_group = (TextView) convertView.findViewById(R.id.tv_group);
ImageView iv_group = (ImageView) convertView.findViewById(R.id.iv_group);
tv_group.setText(groups[groupPosition]);
//控制是否展开图标
if (isExpanded) {
iv_group.setImageResource(R.drawable.expand_iv_up);
} else {
iv_group.setImageResource(R.drawable.expand_iv_down);
}
return convertView;
}
/*#TODO 填充二级列表*/
@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
if (convertView == null) {
convertView = getLayoutInflater().inflate(R.layout.list_item_expandablelistview_child,null);
}
ImageView image = (ImageView) convertView.findViewById(R.id.iv_child);
TextView tv = (TextView) convertView.findViewById(R.id.tv_child);
tv.setText(childs[groupPosition][childPosition]);
return convertView;
}
/*二级列表中每个能否被选中，如果有点击事件一定要设为true*/
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
到这里基本就完成了，最后再配置一下每个二级列表的点击事件即可：
expandableListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
@Override
public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) {
TextView childAt = (TextView)((LinearLayout) v).getChildAt(1);//获得点击列表中TextView的值，需要强转一下，否则找不到getChildAt方法
5 Toast.makeText(ExpandableListViewActivity.this, "点击了 "+childAt.getText()+" 列表", Toast.LENGTH_SHORT).show();
return true;
}
});