make custom scrolling view pager with custom Indicator( using dynamic layout )

 we define one view pager and one custom layout , I am defining that layout at run time and add images on selected item and unselected items. we use deferent -2 images for this.

XML code is given below:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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="match_parent"
    tools:context=".MainActivity">
    <androidx.viewpager2.widget.ViewPager2
        android:id="@+id/viewPager"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_width="match_parent"
        app:layout_constraintBottom_toTopOf="@id/sliderDots"
        android:layout_height="380dp" />

    <LinearLayout
        android:id="@+id/sliderDots"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_gravity="bottom"
        app:layout_constraintTop_toBottomOf="@id/viewPager"
        app:layout_constraintStart_toStartOf="parent"
        android:layout_margin="12dp"
        android:orientation="horizontal" />


</androidx.constraintlayout.widget.ConstraintLayout>

2- Main Activity code(Logic For make selected and unSelected
code ViewPager)
package com.example.viewpager2;

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.content.ContextCompat;
import androidx.viewpager2.widget.ViewPager2;

import android.os.Bundle;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    ViewPager2 viewPager2;
    LinearLayout linearLayout;

    /// make Array list stor images for view pager:
    private ArrayList<RseponseModel> bannerImageList;
    private ViewPagerAdapter adapter;
    /// define one value for traversing loop and add image on view. its size is equal to adapter items
    // size

    int adapterItemCont;

    // make One Array for Storing images for select and un select view pager:
    private ImageView[] dots;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        viewPager2 = (ViewPager2) findViewById(R.id.viewPager);
        linearLayout = (LinearLayout) findViewById(R.id.sliderDots);

        addDataList();
        inViewPager();
        makeCustomLay();
        
        setDataViewPageer();
    }

    private void makeCustomLay() {
        adapterItemCont = adapter.getItemCount();
        dots = new ImageView[adapterItemCont];
        for (int i = 0; i < adapterItemCont; i++) {
            dots[i] = new ImageView(this);
            dots[i].setImageDrawable(getDrawable(R.drawable.nonactive_dots));
            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
            params.setMargins(8, 0, 8, 4);
            linearLayout.addView(dots[i], params);

        }
        dots[0].setImageDrawable(ContextCompat.getDrawable(getApplicationContext(), R.drawable.active_dot));

    }

    private void inViewPager() {
        adapter = new ViewPagerAdapter(this, bannerImageList);
        viewPager2.setAdapter(adapter);

    }

    private void addDataList() {
        bannerImageList = new ArrayList<>();
        bannerImageList.add(new RseponseModel(R.drawable.footerwallet));
        bannerImageList.add(new RseponseModel(R.drawable.garden_amen));
        bannerImageList.add(new RseponseModel(R.drawable.gallary));
        bannerImageList.add(new RseponseModel(R.drawable.footerwallet));
    }

    private void setDataViewPageer() {
        viewPager2.registerOnPageChangeCallback(new ViewPager2.OnPageChangeCallback() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
                super.onPageScrolled(position, positionOffset, positionOffsetPixels);
            }

            @Override
            public void onPageSelected(int position) {
                super.onPageSelected(position);
                for (int i = 0; i < adapterItemCont; i++) {
                    dots[i].setImageDrawable(ContextCompat.getDrawable(getApplicationContext(), R.drawable.nonactive_dots));
                }
                dots[position].setImageDrawable(ContextCompat.getDrawable(getApplicationContext(), R.drawable.active_dot));
                adapter.notifyDataSetChanged();
            }

            @Override
            public void onPageScrollStateChanged(int state) {
                super.onPageScrollStateChanged(state);
            }
        });
    }
}