How to set the ImageView.VISIBLE on the first child of all the Groups and other ChildViews should be hidden In ExpandableListView

Question

Implemented ExpandableListview, I have ImageView on the childView and it should be VISIBLE on the group first child and for other ChildView should be Hidden And after reloading the listView how can I hold the Image status of childView.

Find the below code which I implemented

filterChild.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <TextView
        android:id="@+id/lblListItemFilter"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:paddingLeft="?android:attr/expandableListPreferredChildPaddingLeft"
        android:paddingTop="10dp"
        android:paddingBottom="10dp"
        android:focusable="false"
        android:descendantFocusability="blocksDescendants"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <ImageView
        android:id="@+id/check"
        android:layout_width="15dp"
        android:layout_height="15dp"
        android:layout_gravity="left"
        android:layout_marginEnd="16dp"
        android:background="@drawable/checkmark"
        android:gravity="center"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

Listeners in Activity

expListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {

            @Override
            public boolean onGroupClick(ExpandableListView parent, View v,
                                        int groupPosition, long id) {
                 Toast.makeText(getApplicationContext(),
                 "Group Clicked " + listDataHeader.get(groupPosition),
                 Toast.LENGTH_SHORT).show();

                return false;
            }
        });

        expListView.setOnGroupExpandListener(new ExpandableListView.OnGroupExpandListener() {

            @Override
            public void onGroupExpand(int groupPosition) {
                Toast.makeText(getApplicationContext(),
                        listDataHeader.get(groupPosition) + " Expanded",
                        Toast.LENGTH_SHORT).show();
            }
        });


        expListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {

            @Override
            public boolean onChildClick(ExpandableListView parent, View v,
                                        int groupPosition, int childPosition, long id) {
                // TODO Auto-generated method stub
               System.out.println("childPosition"+listDataChild.get(
                       listDataHeader.get(groupPosition)).get(
                       childPosition));

                Toast.makeText(
                        getApplicationContext(),
                        listDataHeader.get(groupPosition)
                                + " : "
                                + listDataChild.get(
                                listDataHeader.get(groupPosition)).get(
                                childPosition), Toast.LENGTH_SHORT)
                        .show();
                return true;
            }
        });

BaseExpandableListAdapter Class

package com.conduent.conduentebi;

import android.content.Context;
import android.graphics.Typeface;
import android.icu.util.ULocale;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.ImageView;
import android.widget.TextView;

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

public class FilterExpandableListAdapter extends BaseExpandableListAdapter {

    private Context _context;
    private List<String> _listDataHeader; // header titles
    // child data in format of header title, child title
    private HashMap<String, List<String>> _listDataChild;

    private HashMap<Integer, boolean[]> mChildCheckStates;
    private List<ULocale.Category> mGroupCollection;

    public FilterExpandableListAdapter(Context context, List<String> listDataHeader,
                                 HashMap<String, List<String>> listChildData) {
        this._context = context;
        this._listDataHeader = listDataHeader;
        this._listDataChild = listChildData;

        mChildCheckStates = new HashMap<Integer, boolean[]>();
    }

    @Override
    public Object getChild(int groupPosition, int childPosititon) {
        return this._listDataChild.get(this._listDataHeader.get(groupPosition))
                .get(childPosititon);
    }

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

    @Override
    public View getChildView(int groupPosition, int childPosition,
                             boolean isLastChild, View convertView, ViewGroup parent) {

        final int mGroupPosition = groupPosition;
        final int mChildPosition = childPosition;

        ChildViewHolder viewHolder = null;

        final String childText = (String) getChild(groupPosition, childPosition);

        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.filter_child, null);

            System.out.println("mChildPosition"+mChildPosition);

                viewHolder = new ChildViewHolder();

//                viewHolder.checkBox1 = (CheckBox) convertView.findViewById(R.id.check);
//                viewHolder.checkBox1.setFocusable(false);

                viewHolder.mChildText = (TextView) convertView
                        .findViewById(R.id.lblListItemFilter);

                //viewHolder.checkBox1 = (CheckBox)convertView.findViewById(R.id.check);

                convertView.setTag(R.layout.filter_child, viewHolder);
                //viewHolder.checkBox2 = (CheckBox)convertView.findViewById(R.id.check);

        }else {
            viewHolder = (ChildViewHolder) convertView
                    .getTag(R.layout.filter_child);
        }

       // TextView txtListChild = (TextView) convertView
         //       .findViewById(R.id.lblListItemFilter);

        viewHolder.mChildText.setText(childText);




        convertView.setClickable(false);

        return convertView;
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        return this._listDataChild.get(this._listDataHeader.get(groupPosition))
                .size();
    }





    @Override
    public Object getGroup(int groupPosition) {
        return this._listDataHeader.get(groupPosition);
    }

    @Override
    public int getGroupCount() {
        return this._listDataHeader.size();
    }

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

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded,
                             View convertView, ViewGroup parent) {
        String headerTitle = (String) getGroup(groupPosition);
        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.filter_group, null);
        }



        TextView lblListHeader = (TextView) convertView
                .findViewById(R.id.lblListHeaderFilter);
        lblListHeader.setTypeface(null, Typeface.BOLD);
        lblListHeader.setText(headerTitle);

        convertView.setClickable(false);

        return convertView;
    }

    class ChildViewHolder{

        TextView mChildText;
        ImageView checkBox1;

    }

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

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

Answer 1

If you want to hold the old state of the view and show the view accordingly when you reload the screen i would suggest you construct a model to hold your data and make a list of that.

And for any change you should use the list of that model for updated data. This will help you to maintain the state of the different views in your list item.