ExpandableListView用法

     ExpandableListView实现子列表

    1.布局文件:

           <?xml version="1.0" encoding="UTF-8"?>
            <LinearLayout
                    xmlns:android="http://schemas.android.com/apk/res/android"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:background="@color/white"
                    android:orientation="vertical">
                <ExpandableListView
                      android:id="@android:id/list"     //必须如此定义ID
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content">
               </ExpandableListView>
           </LinearLayout>

       2.ExpandableListView适配器 

public class ProvinceAdapter extends BaseExpandableListAdapter{
 
 private Activity activity;
 
 private String[] armTypes = new String[]{"南京","常州","南通"};
 private String[][] arms = new String[][]{
   {"江宁","雨花","下关","白下"},
   {"溧阳","金坛"},
   {"海安","如皋"}
   };
 
 public ProvinceAdapter(Activity activity){
  this.activity = activity;
 }
 
 @Override
 public boolean isChildSelectable(int groupPosition, int childPosition) {
  return true;
 }
 
 @Override
 public boolean hasStableIds() {
  return true;
 }
 
 @Override
 public View getGroupView(int groupPosition, boolean isExpanded,
   View convertView, ViewGroup parent) {
       LinearLayout ll = new LinearLayout(activity);
       ll.setOrientation(LinearLayout.HORIZONTAL);
       ImageView show_or_hideImg = new ImageView(activity);
      if (isExpanded) {//如果父菜单是展开的 则展示向上箭头的图片
          show_or_hideImg.setBackgroundResource(R.drawable.arrow_up);
       }else {
          show_or_hideImg.setBackgroundResource(R.drawable.arrow_down);
        }

  
           TextView textView = new TextView(activity);
            textView.setText(getGroup(groupPosition).toString());
            textView.setTextColor(Color.BLACK);
            textView.setTextSize(16);
            textView.setTypeface(Typeface.DEFAULT_BOLD);
            textView.setPadding(15, 10, 10, 10);
            textView.setGravity(Gravity.CENTER_VERTICAL);
            ll.addView(textView,new LinearLayout.LayoutParams(300,55));
  
           LinearLayout.LayoutParams imgLp = new LinearLayout.LayoutParams(44,LayoutParams.WRAP_CONTENT);
           imgLp.gravity = Gravity.CENTER_VERTICAL|Gravity.CENTER_HORIZONTAL;
           show_or_hideImg.setLayoutParams(imgLp);
           ll.addView(show_or_hideImg);//图片放在右边
           return ll;
 }
 
 @Override
 public long getGroupId(int groupPosition) {
  return groupPosition;
 }
 
 @Override
 public int getGroupCount() {
  return armTypes.length;
 }
 
 @Override
 public Object getGroup(int groupPosition) {
  return armTypes[groupPosition];
 }
 
 @Override
 public int getChildrenCount(int groupPosition) {
  return arms[groupPosition].length;
 }
 
 private TextView getTextView(){
//  AbsListView.LayoutParams lp = new AbsListView.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT,47);
  AbsListView.LayoutParams lp = new AbsListView.LayoutParams((int) (SyncSerUtil.defaultWidth * 0.8),50);
  TextView textView = new TextView(activity);
  textView.setLayoutParams(lp);
  textView.setPadding(38, 10, 0, 10);
  textView.setGravity(Gravity.CENTER_VERTICAL);
  textView.setTextColor(Color.BLACK);
  textView.setTextSize(15);
  return textView;
 }
 
 
 @Override
 public View getChildView(int groupPosition, int childPosition,
   boolean isLastChild, View convertView, ViewGroup parent) {
  TextView textView = getTextView();
  textView.setText(getChild(groupPosition, childPosition).toString());
  return textView;
 }
 
 @Override
 public long getChildId(int groupPosition, int childPosition) {
  return childPosition;
 }
 
 @Override
 public Object getChild(int groupPosition, int childPosition) {
  return arms[groupPosition][childPosition];
 }

}

3.给ExpandableListView设定适配器

provinceListview.setGroupIndicator(null);//去掉自带的图片

provinceListview.setAdapter(new ProvinceAdapter(XXXActivity.this))

4.常用事件

//点击子菜单事件
  provinceListView.setOnChildClickListener(new OnChildClickListener() {
   
   @Override
   public boolean onChildClick(ExpandableListView parent, View v,int groupPosition, int childPosition, long id) {
            Toast.makeText(ChartActivity.this, provinceAdapter.getChild(groupPosition, childPosition).toString(), Toast.LENGTH_LONG).show();
    return false;
       }
     });

//展开收缩子菜单事件(保证当前只展开一个父菜单)
  provinceListView.setOnGroupExpandListener(new OnGroupExpandListener() {
   
   @Override
   public void onGroupExpand(int groupPosition) {
    for (int i = 0; i < provinceAdapter.getGroupCount(); i++) {
     if (i != groupPosition) {
         provinceListView.collapseGroup(i);
     }}});