一种用于垂直滚动展示两级列表的视图，和 ListView 的不同之处就是它可以展示两级列表，分组可以单独展开显示子选项。这些选项的数据是通过 ExpandableListAdapter 关联的。
java写
在这里我用了两个String数组
package com.example.expandablelistr;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnChildClickListener;
import android.widget.Toast;
import android.widget.ExpandableListView.OnGroupClickListener;
import android.widget.TextView;
public class MainActivity extends Activity {
ExpandableListView expandableListView;
String[] groupStrings = {"西游记", "水浒传", "三国演义", "红楼梦"};
String[][] childStrings = {
{"唐三藏", "孙悟空", "猪八戒", "沙和尚"},
{"宋江", "林冲", "李逵", "鲁智深"},
{"曹操", "刘备", "孙权", "诸葛亮", "周瑜"},
{"贾宝玉", "林黛玉", "薛宝钗", "王熙凤"}};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
expandableListView=(ExpandableListView) findViewById(R.id.expandableListView);
myadapter myadapter = new myadapter();
expandableListView.setAdapter(myadapter);
//点击组的监听
expandableListView.setOnGroupClickListener(new OnGroupClickListener() {
@Override
public boolean onGroupClick(ExpandableListView parent, View v,
int groupPosition, long id) {
// TODO Auto-generated method stub
Toast.makeText(getApplication(), groupStrings[groupPosition], 0).show();;
return false;//返回false不然分组不会展开
}
});
expandableListView.setOnChildClickListener(new OnChildClickListener() {
@Override
public boolean onChildClick(ExpandableListView parent, View v,
int groupPosition, int childPosition, long id) {
// TODO Auto-generated method stub
Toast.makeText(getApplication(), childStrings[groupPosition][childPosition], 0).show();;
return false;
}
});
}
class myadapter extends BaseExpandableListAdapter{
//分组的个数
@Override
public int getGroupCount() {
// TODO Auto-generated method stub
return groupStrings.length;
}
//获取指定分组中的子选项的个数
@Override
public int getChildrenCount(int groupPosition) {
// TODO Auto-generated method stub
return childStrings[groupPosition].length;
}
//获取指定的分组数据
@Override
public Object getGroup(int groupPosition) {
// TODO Auto-generated method stub
return groupStrings[groupPosition];
}
//获取指定分组中指定的子选项的数据
@Override
public Object getChild(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return childStrings[groupPosition][childPosition];
}
//获取指定分组的ID
@Override
public long getGroupId(int groupPosition) {
// TODO Auto-generated method stub
return groupPosition;
}
//获取指定分组下的子选项ID
@Override
public long getChildId(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return childPosition;
}
//分组和子选项是否持有稳定的ID,也就是底层数据的改变会不会影响到他们
@Override
public boolean hasStableIds() {
// TODO Auto-generated method stub
return true;
}
//获取指定分组的视图(isExpanded是否扩展)
@Override
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
GroupViewHolder groupViewHolder=null;
if(convertView==null){
convertView=View.inflate(MainActivity.this,R.layout.hzu, null);
groupViewHolder=new GroupViewHolder();
groupViewHolder.tvTitle=(TextView) convertView.findViewById(R.id.label_expand_group);
convertView.setTag(groupViewHolder);
}else{
groupViewHolder = (GroupViewHolder) convertView.getTag();
}
groupViewHolder.tvTitle.setText(groupStrings[groupPosition]);
return convertView;
}
//获取指定分组中的指定子选项的视图
@Override
public View getChildView(int groupPosition, int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ChildViewHolder childViewHolder=null;
if(convertView==null){
childViewHolder=new ChildViewHolder();
convertView=View.inflate(MainActivity.this,R.layout.hzu2, null);
childViewHolder.tvTitle=(TextView)convertView.findViewById(R.id.label_expand_group2);
convertView.setTag(childViewHolder);//else这句话有用
}else{
childViewHolder = (ChildViewHolder) convertView.getTag();
}
Log.e("set", "scoss");
childViewHolder.tvTitle.setText(childStrings[groupPosition][childPosition]);
return convertView;
}
//指定位置上的子元素是否可选中
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return true;
}
}
class GroupViewHolder {
TextView tvTitle;
}
class ChildViewHolder {
TextView tvTitle;
}
}
主xml:
<ExpandableListView
android:id="@+id/expandableListView"
android:layout_width="match_parent"
android:layout_height="match_parent"
></ExpandableListView>
在这里我用了两个Textview.xml
第一个是条目
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/label_expand_group"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:background="@android:color/holo_blue_light"
android:paddingLeft="20dp"
android:textColor="@android:color/white"
android:textSize="30sp"
/>
第二个子目录
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/label_expand_group2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:textColor="#fff"
android:background="@android:color/darker_gray"
android:textSize="20sp"
/>
效果图
image.png
