I have implemented expandablelistview in android app and also implemented divider in it.
I have one problem in not getting the divider between the last item of the child and next group header.
Following image is how I want :

But following is what I'm getting:

Here if you compare both images the divider between the CID and About Set is not coming how to implement that divider ?
Also the groupIndicator is not changing inspite of providing the xml in the groupindicator containing the item tag with 2 different images in android:state_expanded and android:state_empty.
But the property of android:state_expanded and android:state_empty doesn't appear.
It's very easy to Implement.
1- We will add divider in groub_item_layout and child_item_layout:
group_item_layout :
<?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="wrap_content"
    android:background="@color/white"
    android:minHeight="50dp"
    android:orientation="vertical">
    <View
        android:id="@+id/adapter_divider_top"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="#B6B6B6" />
    <TextView
        android:id="@+id/tv_adapter_text"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center_vertical"
        android:paddingBottom="10dp"
        android:paddingLeft="?android:attr/expandableListPreferredItemPaddingLeft"
        android:paddingRight="10dp"
        android:paddingTop="10dp"
        android:text="Home"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:textColor="@color/primary_text" />
</LinearLayout>
child_item_layout :
<?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="wrap_content"
    android:orientation="vertical">
    <TextView
        android:id="@+id/tv_adapter_desc"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:padding="10dp"
        android:text="description"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:textColor="#212121" />
    <View
        android:id="@+id/adapter_divider_bottom"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="@color/divider" />
</LinearLayout>
2- In your Adapter getChildView() and getGroupView() Methods:
 @Override
    public View getGroupView(int groupPosition, boolean isExpanded, View view, ViewGroup viewGroup) {
        if (view == null) {
            view = mInflater.inflate(R.layout.group_item_layout, null);
            mGroupViewHolder = new GroupViewHolder();
            mGroupViewHolder.tvTitle = (TextView) view.findViewById(R.id.tv_adapter_title);
            mGroupViewHolder.dividerTop = view.findViewById(R.id.adapter_divider_top);
            view.setTag(mGroupViewHolder);
        } else {
            mGroupViewHolder = (GroupViewHolder) view.getTag();
        }
        // That if you want to show divider in expanded group only.
        // If you want to show divider in all group items remove this block.
        if (isExpanded) {
            mGroupViewHolder.dividerTop.setVisibility(View.VISIBLE);
        } else {
            mGroupViewHolder.dividerTop.setVisibility(View.INVISIBLE);
        }
        // That if you want to show divider in expanded group only.
        String myTitle = getGroup(groupPosition);
        if(myTitle != null) {
            mGroupViewHolder.tvTitle.setText(myTitle);
        }
        return view;
    }
@Override
    public View getChildView(final int groupPosition, int childPosition, boolean isLastChild, View convertView, final ViewGroup parent) {
        if (view == null) {
            view = mInflater.inflate(R.layout.child_item_layout, null);
            mChildViewHolder = new ChildViewHolder();
            mChildViewHolder.tvDesc = (TextView) view.findViewById(R.id.tv_adapter_desc);
            mChildViewHolder.dividerBottom = view.findViewById(R.id.adapter_divider_bottom);
            view.setTag(mChildViewHolder);
        } else {
            mChildViewHolder = (ChildViewHolder) view.getTag();
        }
        if(isLastChild) {
            mChildViewHolder.dividerBottom.setVisibility(View.VISIBLE);
        } else {
            mChildViewHolder.dividerBottom.setVisibility(View.INVISIBLE);
        }
        Timesheet timesheet = getChild(groupPosition, childPosition);
        if(timesheet != null) {
            mChildViewHolder.tvDesc.setText(timesheet.getDescription());
        }
        return view;
    }
Hope this helps anyone.
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