GridView in Android

GridView is a ViewGroup that displays items in a two-dimensional, scrollable grid. The grid items are automatically inserted to the layout using a ListAdapter

 activity_main.xml

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<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:showIn="@layout/activity_main" tools:context=".MainActivity">

    <GridView
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:numColumns="3"
        android:id="@+id/gridView" />
</LinearLayout>

MainActivity.Java

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package com.android.anil.gridview;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {
    GridView gridView;
    int[] images={R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,R.mipmap.ic_launcher};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        gridView=(GridView)findViewById(R.id.gridView);
        Myadapter myadapter=new Myadapter();
        gridView.setAdapter(myadapter);
    }
    class Myadapter extends BaseAdapter{
        @Override
        public int getCount() {
            return images.length;
        }

        @Override
        public Object getItem(int position) {
            return null;
        }

        @Override
        public long getItemId(int position) {
            return 0;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView imageView=new ImageView(getApplicationContext());
            imageView.setImageResource(images[position]);
            return imageView;
        }
    }

}

Output is:
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