A 3 level expandable list view

activity_main.xml

<RelativeLayout 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: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">

    <ExpandableListView android:id="@+id/mainList"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></ExpandableListView>
</RelativeLayout>

row_first.xml

<?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="100dp"
              android:background="@android:color/holo_orange_dark"
              android:padding="10dp"
              android:orientation="vertical">

    <TextView
        android:id="@+id/eventsListEventRowText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="20dp"
        android:textColor="@android:color/white"
        android:textSize="18sp"/>
</LinearLayout>

row_second.xml

<?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="@android:color/holo_blue_bright"
              android:padding="10dp"
              android:orientation="vertical">

    <TextView
        android:id="@+id/eventsListEventRowText"
        android:paddingLeft="20dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textColor="@android:color/white"
        android:textSize="14sp"/>
</LinearLayout>

row_third.xml

<?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:padding="10dp"
              android:orientation="vertical"
              android:background="@android:color/holo_green_dark">

    <TextView
        android:id="@+id/eventsListEventRowText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textColor="@android:color/white"
        android:textSize="24sp"/>
</LinearLayout>

ThreeLevelExpandableListView.java

package net.stf.threelevelexpandablelistview;

import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;

/**
 * New and improved. Feel free to contact me if you have any questions.
 */

public class ThreeLevelExpandableListView extends AppCompatActivity {

    public static final int FIRST_LEVEL_COUNT = 6;
    public static final int SECOND_LEVEL_COUNT = 4;
    public static final int THIRD_LEVEL_COUNT = 20;
    private ExpandableListView expandableListView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        expandableListView = (ExpandableListView) findViewById(R.id.mainList);
        expandableListView.setAdapter(new ParentLevel(this));
    }

    public class ParentLevel extends BaseExpandableListAdapter {

        private Context context;

        public ParentLevel(Context context) {
            this.context = context;
        }

        @Override
        public Object getChild(int arg0, int arg1) {
            return arg1;
        }

        @Override
        public long getChildId(int groupPosition, int childPosition) {
            return childPosition;
        }

        @Override
        public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
            SecondLevelExpandableListView secondLevelELV = new SecondLevelExpandableListView(MainActivity.this);
            secondLevelELV.setAdapter(new SecondLevelAdapter(context));
            secondLevelELV.setGroupIndicator(null);
            return secondLevelELV;
        }

        @Override
        public int getChildrenCount(int groupPosition) {
            return SECOND_LEVEL_COUNT;
        }

        @Override
        public Object getGroup(int groupPosition) {
            return groupPosition;
        }

        @Override
        public int getGroupCount() {
            return FIRST_LEVEL_COUNT;
        }

        @Override
        public long getGroupId(int groupPosition) {
            return groupPosition;
        }

        @Override
        public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
            if (convertView == null) {
                LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                convertView = inflater.inflate(R.layout.row_first, null);
                TextView text = (TextView) convertView.findViewById(R.id.eventsListEventRowText);
                text.setText("FIRST LEVEL");
            }
            return convertView;
        }

        @Override
        public boolean hasStableIds() {
            return true;
        }

        @Override
        public boolean isChildSelectable(int groupPosition, int childPosition) {
            return true;
        }
    }

    public class SecondLevelExpandableListView extends ExpandableListView {

        public SecondLevelExpandableListView(Context context) {
            super(context);
        }

        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            //999999 is a size in pixels. ExpandableListView requires a maximum height in order to do measurement calculations. 
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(999999, MeasureSpec.AT_MOST);
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        }
    }

    public class SecondLevelAdapter extends BaseExpandableListAdapter {

        private Context context;

        public SecondLevelAdapter(Context context) {
            this.context = context;
        }

        @Override
        public Object getGroup(int groupPosition) {
            return groupPosition;
        }

        @Override
        public int getGroupCount() {
            return 1;
        }

        @Override
        public long getGroupId(int groupPosition) {
            return groupPosition;
        }

        @Override
        public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
            if (convertView == null) {
                LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                convertView = inflater.inflate(R.layout.row_third, null);
                TextView text = (TextView) convertView.findViewById(R.id.eventsListEventRowText);
                text.setText("SECOND LEVEL");
            }
            return convertView;
        }

        @Override
        public Object getChild(int groupPosition, int childPosition) {
            return childPosition;
        }

        @Override
        public long getChildId(int groupPosition, int childPosition) {
            return childPosition;
        }

        @Override
        public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
            if (convertView == null) {
                LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                convertView = inflater.inflate(R.layout.row_second, null);
                TextView text = (TextView) convertView.findViewById(R.id.eventsListEventRowText);
                text.setText("THIRD LEVEL");
            }
            return convertView;
        }

        @Override
        public int getChildrenCount(int groupPosition) {
            return THIRD_LEVEL_COUNT;
        }

        @Override
        public boolean hasStableIds() {
            return true;
        }

        @Override
        public boolean isChildSelectable(int groupPosition, int childPosition) {
            return true;
        }
    }
}

HI I've set OnChildClickListener but it does not work. Can you please help?

First Thanks for nice code..I would like to know how will we populate list dynamically.

Nice Tutorial. Works charm. Thanks for code

How to populate Dynamically values..??pls help me out...

At third level we have multiple child with image view , the issue is that when image loading finish third child row added multiple time.

How to use Dynamical Values...?
and ClickListner

Is it works fine in ScrollView?

can you explain same in terms of list and model object instead of integer count

please can you explain by using ArrayList as dataresource ..

for SecondLevelAdapter group view is shown for group postion 0 only. Please tell me why it is not called for other positions

For dynamic make we should use recursion...

I have created a repo to add dynamic data in this list, it works fine until level 3. Kindly look at this repo (https://github.com/talhahasanzia/Three-Level-Expandible-Listview) and see if you can contribute. The code is not very optimized since my primary goal is to get the list working.
@shripaljadhav @shripaljadhav @wasimdivum @ShrikantBadwaik-007 @ashokbg

@anandtaji I have tried recursive approach (calling other adapter in getChildView() ) and it failed badly.

Thanks alot for such a nice code.....it really helped me out.

Muchas gracias!

Thank u so much!! lml

Hello sir, I have implement this code and working as well. but I have issue getting double time sub group to show selected child.
I have modify some in my code. Could you please check that Why I am getting that?

protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        widthMeasureSpec = MeasureSpec.makeMeasureSpec(widthMeasureSpec,
                MeasureSpec.AT_MOST);
        heightMeasureSpec = MeasureSpec.makeMeasureSpec(totalHeight,
                MeasureSpec.AT_MOST);
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

This changes is in CustExpListview.

if (isSelected) {
            mCustExpListview.expandGroup(1);
}

This changes is in Parend Adapter getChildView method.

First Thanks for the nice code. .and
I would like to know how to do a miltilevel expandable listview?
Please help me out...

hi,
Cool sample..!!
i used this classes, and added dynamic data to it.
I faced two issues;

1. texts gets random; common and well known listview problem; solved by adding viewholder and setTag-getTag approach.
2. when all three levels of a item is opened; and list is scrolled, and then scrolled backed; thrid level of list gets collapsed (Mostly due to re-rendering of listview cells)

Is there any way to maintain, collapsed and expanded state for thrid level?

Thanks in advance.

how to click event on 3rd level child please check sir
Thanks i am waiting your response

It means u are a master developer in android
thanks for your tutorial

its a hundreds dollar code

nice code, thanks.

can yuo help ma to three level expandable list view inside drawer layout