<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/idRLBack"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <!--Image view for displaying our image-->
    <ImageView
        android:id="@+id/idIVImage"
        android:layout_width="200dp"
        android:layout_height="200dp"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="70dp"
        android:src="@drawable/logo1" />

    <!--linear layout for our buttons to 
        change image and layout colors-->
    <LinearLayout
        android:id="@+id/idLL"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/idIVImage"
        android:layout_centerHorizontal="true"
        android:layout_margin="10dp"
        android:orientation="horizontal"
        android:weightSum="2">

        <!--first button for our first image-->
        <Button
            android:id="@+id/idBtnChangeImg"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:layout_weight="1"
            android:text="Image 1"
            android:textAllCaps="false" />

        <!--second button for our second image-->
        <Button
            android:id="@+id/idBtnChangeImg2"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:layout_weight="1"
            android:text="Image 2"
            android:textAllCaps="false" />
    </LinearLayout>

    <!--sample text view for heading-->
    <TextView
        android:id="@+id/idTVGFG"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/idLL"
        android:layout_margin="4dp"
        android:padding="4dp"
        android:text="Welcome to Geeks for Geeks"
        android:textAlignment="center"
        android:textSize="25sp" />

    <!--sample text view for second heading-->
    <TextView
        android:id="@+id/idTVHead"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/idTVGFG"
        android:layout_margin="3dp"
        android:padding="4dp"
        android:text="Geeks For Geeks Carnival"
        android:textAlignment="center" />

</RelativeLayout>

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;
import androidx.palette.graphics.Palette;

public class MainActivity extends AppCompatActivity {

    // creating variables for our UI components..
    private TextView headTV, gfgTV;
    private ImageView gfgIV;
    private Button changeBtn, changeBtn2;
    private RelativeLayout backRL;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // initializing all our variables with their ids.
        headTV = findViewById(R.id.idTVHead);
        gfgTV = findViewById(R.id.idTVGFG);
        gfgIV = findViewById(R.id.idIVImage);
        backRL = findViewById(R.id.idRLBack);
        changeBtn = findViewById(R.id.idBtnChangeImg);
        changeBtn2 = findViewById(R.id.idBtnChangeImg2);

        // on below line we are decoding our image from image resource.
        Bitmap bitmap1 = BitmapFactory.decodeResource(getResources(), R.drawable.logo1);
        Bitmap bitmap2 = BitmapFactory.decodeResource(getResources(), R.drawable.logo2);

        // Get bitmap from drawable resources
        // on below line we are calling a method
        // to change the layout color according to first image.
        createPaletteAsync(bitmap1);

        // on below line we are setting 
        // bitmap to our image view.
        gfgIV.setImageBitmap(bitmap1);

        // on below line we are adding click listener to our button1.
        changeBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                // inside on click we are calling a second method 
                // to change our layout colors with second image bitmaps. .
                createDarkPaletteAsync(bitmap2);

                // on below line we are setting bitmap to our image view.
                gfgIV.setImageBitmap(bitmap2);
            }
        });

        // adding on click listener for our second button.
        changeBtn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                // on below line we are calling a method to change
                // our layout colors and we are passing our first image bitmap.
                createPaletteAsync(bitmap1);

                // on below line we are setting 
                // the bitmap to our image view.
                gfgIV.setImageBitmap(bitmap1);
            }
        });
    }

    public void createDarkPaletteAsync(Bitmap bitmap) {

        // on below line we are calling a palette 
        // method from bitmap to get colors from our image.
        Palette.from(bitmap).generate(new Palette.PaletteAsyncListener() {
            public void onGenerated(Palette p) {

                // Use generated instance
                // on below line we are passing
                // a default value to it.
                int defaultValue = 0x000000;

                // on below line we are adding colors to our different views.
                headTV.setTextColor(p.getLightVibrantColor(defaultValue));
                gfgTV.setTextColor(p.getLightVibrantColor(defaultValue));
                backRL.setBackgroundColor(p.getDarkVibrantColor(defaultValue));
                changeBtn.setTextColor(p.getDarkVibrantColor(defaultValue));
                changeBtn.setBackgroundColor(p.getLightVibrantColor(defaultValue));
                changeBtn2.setTextColor(p.getDarkVibrantColor(defaultValue));
                changeBtn2.setBackgroundColor(p.getLightVibrantColor(defaultValue));
            }
        });
    }

    public void createPaletteAsync(Bitmap bitmap) {
        // on below line we are calling a palette method
        // from bitmap to get colors from our image.
        Palette.from(bitmap).generate(new Palette.PaletteAsyncListener() {
            public void onGenerated(Palette p) {

                // Use generated instance
                // on below line we are passing
                // a default value to it.
                int defaultValue = 0x000000;

                // on below line we are adding colors to our different views.
                headTV.setTextColor(p.getDarkVibrantColor(defaultValue));
                gfgTV.setTextColor(p.getDominantColor(defaultValue));
                backRL.setBackgroundColor(p.getLightVibrantColor(defaultValue));
                changeBtn.setTextColor(p.getLightMutedColor(defaultValue));
                changeBtn.setBackgroundColor(p.getDarkVibrantColor(defaultValue));
                changeBtn2.setTextColor(p.getLightMutedColor(defaultValue));
                changeBtn2.setBackgroundColor(p.getDarkVibrantColor(defaultValue));

            }
        });
    }
}