<?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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="10dp">

    <ImageView
        android:id="@+id/slider_image"
        android:layout_width="0dp"
        android:layout_height="400dp"
        android:layout_marginTop="32dp"
        android:padding="20dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:srcCompat="@drawable/sit_back_and_relax" />

    <TextView
        android:id="@+id/slider_heading"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="174dp"
        android:layout_marginLeft="174dp"
        android:layout_marginEnd="178dp"
        android:layout_marginRight="178dp"
        android:fontFamily="@font/brandon_grotesque_black"
        android:gravity="center"
        android:text="TextView"
        android:textSize="36sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.471"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/slider_image" />

    <TextView
        android:id="@+id/slider_desc"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="176dp"
        android:layout_marginLeft="176dp"
        android:layout_marginEnd="176dp"
        android:layout_marginRight="176dp"
        android:gravity="center"
        android:padding="10dp"
        android:text="@string/first_slide_desc"
        android:textSize="14sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/slider_heading" />
</androidx.constraintlayout.widget.ConstraintLayout>

import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager.widget.ViewPager;
import android.content.Intent;
import android.os.Bundle;
import android.text.Html;
import android.view.View;
import android.view.WindowManager;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

import com.taimoorsikander.cityguide.HelperClasses.SliderAdapter;
import com.taimoorsikander.cityguide.R;
import com.taimoorsikander.cityguide.User.UserDashboard;

public class OnBoarding extends AppCompatActivity {

    //Variables
    ViewPager viewPager;
    LinearLayout dotsLayout;
    SliderAdapter sliderAdapter;
    TextView[] dots;
    Button letsGetStarted;
    Animation animation;
    int currentPos;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_on_boarding);

        //Hooks
        viewPager = findViewById(R.id.slider);
        dotsLayout = findViewById(R.id.dots);
        letsGetStarted = findViewById(R.id.get_started_btn);

        //Call adapter
        sliderAdapter = new SliderAdapter(this);
        viewPager.setAdapter(sliderAdapter);

        //Dots
        addDots(0);
        viewPager.addOnPageChangeListener(changeListener);
    }

    public void skip(View view) {
        startActivity(new Intent(this, UserDashboard.class));
        finish();
    }

    public void next(View view) {
        viewPager.setCurrentItem(currentPos + 1);
    }

    private void addDots(int position) {

        dots = new TextView[4];
        dotsLayout.removeAllViews();

        for (int i = 0; i < dots.length; i++) {
            dots[i] = new TextView(this);
            dots[i].setText(Html.fromHtml("&#8226;"));
            dots[i].setTextSize(35);

            dotsLayout.addView(dots[i]);
        }

        if (dots.length > 0) {
            dots[position].setTextColor(getResources().getColor(R.color.colorPrimaryDark));
        }

    }

    ViewPager.OnPageChangeListener changeListener = new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

        }

        @Override
        public void onPageSelected(int position) {
            addDots(position);
            currentPos = position;

            if (position == 0) {
                letsGetStarted.setVisibility(View.INVISIBLE);
            } else if (position == 1) {
                letsGetStarted.setVisibility(View.INVISIBLE);
            } else if (position == 2) {
                letsGetStarted.setVisibility(View.INVISIBLE);
            } else {
                animation = AnimationUtils.loadAnimation(OnBoarding.this, R.anim.bottom_anim);
                letsGetStarted.setAnimation(animation);
                letsGetStarted.setVisibility(View.VISIBLE);
            }

        }

        @Override
        public void onPageScrollStateChanged(int state) {

        }
    };

}