Detect user action on ExpandableListView, with various Listeners

ExpandableListView with Listeners

package com.example.androidexpandablelistview;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnChildClickListener;
import android.widget.ExpandableListView.OnGroupClickListener;
import android.widget.ExpandableListView.OnGroupCollapseListener;
import android.widget.ExpandableListView.OnGroupExpandListener;
import android.widget.TextView;

public class MainActivity extends Activity {
 
 MyBaseExpandableListAdapter myBaseExpandableListAdapter;
    ExpandableListView myExpandableListView;
    List<String> myListForGroup;
    HashMap<String, List<String>> myMapForChild;
 
    TextView info;
    
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  
  info = (TextView)findViewById(R.id.info);
  
  myExpandableListView = (ExpandableListView)
    findViewById(R.id.myexpandablelistview);
 
        initData();
 
        myBaseExpandableListAdapter = new 
          MyBaseExpandableListAdapter(this, myListForGroup, myMapForChild);
 
        myExpandableListView.setAdapter(myBaseExpandableListAdapter);
        
        myExpandableListView.setOnChildClickListener(myOnChildClickListener);
        myExpandableListView.setOnGroupClickListener(myOnGroupClickListener);
        myExpandableListView.setOnGroupCollapseListener(myOnGroupCollapseListener);
        myExpandableListView.setOnGroupExpandListener(myOnGroupExpandListener);
 }
 
 private void initData() {
  myListForGroup = new ArrayList<String>();
  myMapForChild = new HashMap<String, List<String>>();

        List<String> listGroupA = new ArrayList<String>();
        listGroupA.add("A - 1");
        listGroupA.add("A - 2");
        listGroupA.add("A - 3");

        List<String> listGroupB = new ArrayList<String>();
        listGroupB.add("B - 1");
 
        List<String> listGroupC = new ArrayList<String>();
        listGroupC.add("C - 1");
        listGroupC.add("C - 2");
        
        myListForGroup.add("Group A");
        myListForGroup.add("Group B");
        myListForGroup.add("Group C");
        
        myMapForChild.put(myListForGroup.get(0), listGroupA);
        myMapForChild.put(myListForGroup.get(1), listGroupB);
        myMapForChild.put(myListForGroup.get(2), listGroupC);
    }
 
 OnChildClickListener myOnChildClickListener =
  new OnChildClickListener(){

   @Override
   public boolean onChildClick(ExpandableListView parent, 
    View v, int groupPosition, int childPosition, long id) {
    String strChild = (String)myBaseExpandableListAdapter
      .getChild(groupPosition, childPosition);
    info.setText("child clicked: " + strChild);
    return true;
   }};
   
 OnGroupClickListener myOnGroupClickListener =
  new OnGroupClickListener(){

   @Override
   public boolean onGroupClick(ExpandableListView parent, 
     View v, int groupPosition, long id) {
    String strGroup = (String)myBaseExpandableListAdapter
      .getGroup(groupPosition);
    info.setText("group clicked: " + strGroup);
    
    return false;
    //return false
    //otherwise, group will not expand when user click on it
   }};
  
 OnGroupCollapseListener myOnGroupCollapseListener =
  new OnGroupCollapseListener(){

   @Override
   public void onGroupCollapse(int groupPosition) {
    info.setText("group collapse: " + groupPosition);
   }};
   
 OnGroupExpandListener myOnGroupExpandListener =
  new OnGroupExpandListener(){

   @Override
   public void onGroupExpand(int groupPosition) {
    info.setText("group expand: " + groupPosition);
   }};

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="android-coding.blogspot.com"
        android:textStyle="bold" />

    <TextView
        android:id="@+id/info"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    
    <ExpandableListView
        android:id="@+id/myexpandablelistview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</LinearLayout>