Android: Test Ads not displaying

Question

i am trying to add Ads to my current activity but the activity is not showing any Ad . i have also add internet permission to Android Manifest.xml

Here is my

.Gradle File

 apply plugin: 'com.android.application'

    android {
        compileSdkVersion 23
        buildToolsVersion "23.0.0"

        defaultConfig {
            applicationId "sms.and.call.alert.flashlight.lpa.com.myapplication"
            minSdkVersion 15
            targetSdkVersion 23
            versionCode 1
            versionName "1.0"
        }
        buildTypes {
            release {
                minifyEnabled false
                proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
            }
        }
    }

    dependencies {
        compile fileTree(dir: 'libs', include: ['*.jar'])
        testCompile 'junit:junit:4.12'
        compile 'com.google.android.gms:play-services:9.6.0'

        compile 'com.google.firebase:firebase-ads:9.6.0'
    }

This is MainActivity

  public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        MobileAds.initialize(getApplicationContext(), "ca-app-pub-3940256099942544~3347511713");
        AdView mAdView = (AdView) findViewById(R.id.adView);
        AdRequest request = new AdRequest.Builder()
                .addTestDevice(AdRequest.DEVICE_ID_EMULATOR)        // All emulators
                  // An example device ID
                .build();
        mAdView.loadAd(request);

    }
}

This is MainActivity.xml

<?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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="sms.and.call.alert.flashlight.lpa.com.myapplication.MainActivity">
    <com.google.android.gms.ads.AdView
        android:id="@+id/adView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_alignParentBottom="true"
        ads:adSize="BANNER"
        ads:adUnitId="@string/banner_ad_unit_id">
    </com.google.android.gms.ads.AdView>
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!" />
</RelativeLayout>

Answer 1

Maybe you forgot to load the Ad by calling:

AdView mAdView = (AdView) findViewById(R.id.adView);
mAdView.loadAd(request);

Answer 2

Admob-Firebase initial configuration guide

updated 10/04/2016 - MM/dd/yyyy

Step 1 : Be sure to have the latest version of Google Play Services and Google Repository

Step 2 : Put the google-services.json in the app folder after you had created the project on Firebase console
More Info:https://firebase.google.com/docs/android/setup#add_firebase_to_your_app

Step 3 : Set up your project level build.gradle as below.
More Info: https://firebase.google.com/docs/android/setup#add_the_sdk

buildscript {
    // ...
    dependencies {
        classpath 'com.android.tools.build:gradle:2.2.0'
        // ...
        classpath 'com.google.gms:google-services:3.0.0'
    }
}

Step 4 : Setup your app level build.gradle as below:
More info: https://firebase.google.com/docs/admob/android/quick-start#integrate_firebase_and_the_mobile_ads_sdk

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.2"

    defaultConfig {
        applicationId "your.package.app"
        minSdkVersion 9
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: '*.jar')

    compile 'com.google.firebase:firebase-ads:9.0.0'
}

apply plugin: 'com.google.gms.google-services'

Step 5 : Add those permissions to the AndroidManifest if they are not present yet

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

Moreover be sure that your package name in the AndroidManifest match the applicationId of you app build.gradle or you will get a compilation error.

Step 6 : Continue to follow the Quick-Start tutorial and learn how to create Ad-Units to show ads on your views: https://firebase.google.com/docs/admob/android/quick-start

Step 7 : If you still have compile time problems, check those really usefull and common-case threads and examples:
Manifest and applicationId problems: https://stackoverflow.com/a/37177173/2910520,
Multiple flavors problems: https://stackoverflow.com/a/34990999/2910520
Google Admob examples:https://github.com/googleads/googleads-mobile-android-examples