2018-12-16_Android image change using button

package com.mukeshdak.rishivajpayee;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

    public void changeImg(View view){
        int[] images = new int[] {R.drawable.r1, R.drawable.r2, R.drawable.r3, R.drawable.r4, R.drawable.r5, R.drawable.r6, R.drawable.r7, R.drawable.r8};
        // Get a random between 0 and images.length-1
        int imageId = (int)(Math.random() * images.length);

        ImageView image = (ImageView) findViewById(R.id.imageView1);
        image.setImageResource(images[imageId]);
    }

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