第一步创建布局
主布局
<ExpandableListView
android:id="@+id/expend_list"
android:layout_width="match_parent"
android:layout_height="match_parent"></ExpandableListView>父item布局
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/label_group_normal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@android:color/holo_blue_light"
android:gravity="center_vertical"
android:paddingBottom="8dp"
android:paddingLeft="32dp"
android:paddingTop="8dp"
android:textColor="@android:color/white"
android:textSize="20sp"
tools:text="测试数据"/>
子item布局
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/expand_child"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:textSize="16sp"
android:paddingTop="8dp"
android:paddingBottom="8dp"
tools:text="测试数据"/>
第二步适配器
public class MyExtendableListViewAdapter extends BaseExpandableListAdapter {
@Override
// 获取分组的个数
public int getGroupCount() {
return groupString.length;
}
//获取指定分组中的子选项的个数
@Override
public int getChildrenCount(int groupPosition) {
return childString[groupPosition].length;
}
// 获取指定的分组数据
@Override
public Object getGroup(int groupPosition) {
return groupString[groupPosition];
}
//获取指定分组中的指定子选项数据
@Override
public Object getChild(int groupPosition, int childPosition) {
return childString[groupPosition][childPosition];
}
//获取指定分组的ID, 这个ID必须是唯一的
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
//获取子选项的ID, 这个ID必须是唯一的
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
//分组和子选项是否持有稳定的ID, 就是说底层数据的改变会不会影响到它们
@Override
public boolean hasStableIds() {
return true;
}
/**
*
* 获取显示指定组的视图对象
*
* @param groupPosition 组位置
* @param isExpanded 该组是展开状态还是伸缩状态
* @param convertView 重用已有的视图对象
* @param parent 返回的视图对象始终依附于的视图组
*/
// 获取显示指定分组的视图
@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
GroupViewHolder groupViewHolder;
if (convertView == null){
convertView = LayoutInflater.from(parent.getContext()).inflate(R.layout.partent_item,parent,false);
groupViewHolder = new GroupViewHolder();
groupViewHolder.tvTitle = (TextView)convertView.findViewById(R.id.label_group_normal);
convertView.setTag(groupViewHolder);
}else {
groupViewHolder = (GroupViewHolder)convertView.getTag();
}
groupViewHolder.tvTitle.setText(groupString[groupPosition]);
return convertView;
}
/**
*
* 获取一个视图对象，显示指定组中的指定子元素数据。
*
* @param groupPosition 组位置
* @param childPosition 子元素位置
* @param isLastChild 子元素是否处于组中的最后一个
* @param convertView 重用已有的视图(View)对象
* @param parent 返回的视图(View)对象始终依附于的视图组
* @return
* @see android.widget.ExpandableListAdapter#getChildView(int, int, boolean, android.view.View,
* android.view.ViewGroup)
*/
//取得显示给定分组给定子位置的数据用的视图
@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
ChildViewHolder childViewHolder;
if (convertView==null){
convertView = LayoutInflater.from(parent.getContext()).inflate(R.layout.child_item,parent,false);
childViewHolder = new ChildViewHolder();
childViewHolder.tvTitle = (TextView)convertView.findViewById(R.id.expand_child);
convertView.setTag(childViewHolder);
}else {
childViewHolder = (ChildViewHolder) convertView.getTag();
}
childViewHolder.tvTitle.setText(childString[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) {
return true;
}
class GroupViewHolder {
TextView tvTitle;
}
class ChildViewHolder {
TextView tvTitle;
}
}
第三步使用及设置数据源
public String[] groupString = {"射手", "辅助", "坦克", "法师"};
public String[][] childString = {
{"孙尚香", "后羿", "马可波罗", "狄仁杰"},
{"孙膑", "蔡文姬", "鬼谷子", "杨玉环"},
{"张飞", "廉颇", "牛魔", "项羽"},
{"诸葛亮", "王昭君", "安琪拉", "干将"}
};
expandableListView=findViewById(R.id.expend_list);
expandableListView.setAdapter(new MyExtendableListViewAdapter());
//设置分组的监听
expandableListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
@Override
public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {
Toast.makeText(getApplicationContext(), groupString[groupPosition], Toast.LENGTH_SHORT).show();
return false;
}
});
expandableListView.setOnGroupExpandListener(new ExpandableListView.OnGroupExpandListener() {
@Override
public void onGroupExpand(int groupPosition) {
int count = new MyExtendableListViewAdapter().getGroupCount();
for(int i = 0;i < count;i++){
if (i!=groupPosition){
expandableListView.collapseGroup(i);
}
}
}
});
//设置子项布局监听
expandableListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
@Override
public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) {
Toast.makeText(getApplicationContext(), childString[groupPosition][childPosition], Toast.LENGTH_SHORT).show();
return true;
}
});
其中设置单个展开代码为：
expandableListView.setOnGroupExpandListener(new ExpandableListView.OnGroupExpandListener() {
@Override
public void onGroupExpand(int groupPosition) {
int count = new MyExtendableListViewAdapter().getGroupCount();
for(int i = 0;i < count;i++){
if (i!=groupPosition){
expandableListView.collapseGroup(i);
}
}
}
});
设置箭头在右边在主布局和父item布局中加入
android:layoutDirection="rtl"