Android | AdMob Interstitial Ads for Android Studio

Interstitial ads are full-screen ads that cover the whole UI of the app. This article shows you how to integrate Interstitial ads from AdMob into an Android app. Example – First Create a new Project in Android Studio and add the following codes to import the google Mobile Ads SDK. In the project-level build.gradle file, add the highlighted code to the allprojects section. 

Java

allprojects
{
    repositories
    {
        google()
            jcenter()
                maven
        {
            url "https://maven.google.com"
        }
    }
}

In the app-level build.gradle file, add the highlighted code to dependencies section. 

Java

dependencies
{
implementation fileTree (dir : 'libs', include : [ '*.jar' ])
implementation 'com.android.support:appcompat-v7:26.1.0'
compile 'com.google.android.gms:play-services-ads:15.0.0'

Add the following code to Main Activity to initialize Mobile Ads SDK (this only needs to be done once in app lifecycle). You can find the app’s App ID in AdMob console. 

Java

package org.geeksforgeeks.geeksforgeeks;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import com.google.android.gms.ads.MobileAds;

public class MainActivity extends AppCompatActivity
{
    protected void onCreate (Bundle savedInstanceState)
    {
        super.onCreate (savedInstanceState);
        setContentView (R.layout.activity_main);

        // Initialize the Mobile Ads SDK
        MobileAds.initialize (this, getString (R.string.admob_app_id));
    }
}

Add the highlighted code to Main Activity to show Interstitial Ad: MainActivity.class –

JAVA

package org.geeksforgeeks.geeksforgeeks;

import android.os.Bundle;
import androidx.appcompat.app.AppCompatActivity;

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

public class MainActivity extends AppCompatActivity {

    private InterstitialAd interstitial;

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

        // Initialize the Mobile Ads SDK
        MobileAds.initialize(this, getString(R.string.admob_app_id));

        // create ad request
        AdRequest adIRequest = new AdRequest.Builder().build();

        // Create an instance of the InterstitialAd object
        interstitial = new InterstitialAd(MainActivity.this);

        // Set the Ad Unit ID
        interstitial.setAdUnitId(getString(R.string.admob_interstitial_id));

        // Load the Interstitial Ad
        interstitial.loadAd(adIRequest);

        // Prepare an Interstitial Ad Listener
        interstitial.setAdListener(new AdListener() {
            @Override
            public void onAdLoaded() {
                // Call displayInterstitial() function when the Ad loads
                displayInterstitial();
            }
        });
    }

    public void displayInterstitial() {
        // If Interstitial Ads are loaded then show them, otherwise do nothing.
        if (interstitial.isLoaded()) {
            interstitial.show();
        }
    }
}

Add the Admob App Id and Interstitial Ad Id to string.xml strings.xml –

XML

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="admob_app_id">
        ca-app-pub-3940256099942544~3347511713</string>
    <string name="admob_interstitial_id">
        ca-app-pub-3940256099942544/1033173712</string>
    <!-- ca-app-pub-3940256099942544~3347511713
                          this is your admob app id -->
    <!-- ca-app-pub-3940256099942544/1033173712
              this is your admob Interstitial ad id -->
</resources>