Display Interstitial Ads in AdMob in Android

Create Project

Create new project in Android Studio with steps as below:

Step 1: Input Project Name and Select Project Location

Step 2: Select SDK for Android App

Step 3: Select Default Activity for App

Step 4: Finish create project

Add Strings

Open res\values\strings.xml file and add new string as below:

<resources>
    <string name="app_name">Learn Android with Real Apps</string>
    <string name="interstitial_ad_unit_id">ca-app-pub-3940256099942544/1033173712</string>
</resources>

Add Library as Dependencies

Open build.gradle file in Gradle Scripts and add new library as below:

implementation 'com.google.android.gms:play-services-ads:11.0.1'

Manifest Permissions

Open AndroidManifest.xml file in manifest folder, add permissions and google map api as below:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="android.demo.learnandroidwithrealapps">

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.INTERNET" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>

</manifest>

Main Activity Layout

Open res\layout\activity_main.xml file and create layout as below:

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

</RelativeLayout>

Main Activity Class

Add code to MainActivity.java in android.demo.learnandroidwithrealapps package as below:

package android.demo.learnandroidwithrealapps;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import com.google.android.gms.ads.AdListener;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.InterstitialAd;

public class MainActivity extends AppCompatActivity {

    private InterstitialAd interstitialAd;

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

    private void initView() {
        interstitialAd = new InterstitialAd(this);
        interstitialAd.setAdUnitId(getString(R.string.interstitial_ad_unit_id));
        interstitialAd.loadAd(new AdRequest.Builder().build());
        interstitialAd.setAdListener(new AdListener() {
            public void onAdLoaded() {
                if (interstitialAd.isLoaded()) {
                    interstitialAd.show();
                }
            }
        });
    }

}

Structure of Project

Run App

Load Main Activity