Xamarin Forms (1)


How To: Add AdMob to your Xamarin Forms app

One of the first things people think about when developing for a new platform / using a new technology is monetization; and in my case the question is: how easy is it to integrate AdMob? For Xamarin Forms the answer would be: “It depends” – it depends on luck & on the complexity of what you want to achieve; but I will detail this as we move along.

The first thing you need to do is add the required components to your projects. For this walktrough I will be using Visual Studio but it should be relatively the same when using Xamarin Studio. Here, things go separate ways for each of the platforms:

  • for Android – add the Google Play Services component
  • for iOS – add the AdMob component
  • for Windows Phone – download the SDK from here and add it as a reference

By now, you Android project should no longer be building & you should be receiving a COMPILETODALVIK : UNEXPECTED TOP-LEVEL error. To fix that, go into your Droid project properties, select the Android Options tab and then under Advanced modify the value for the Java Max Heap Size to 1G. Your project should now build without any errors.

Next, inside your shared / PCL project add a new Content View and call it AdMobView. Remove the code generated inside it’s constructor & it should look like this:

public class AdMobView : ContentView
{
    public AdMobView() { }
}

Add this new view to your page. In XAML you can do it like this:

<controls:AdMobView WidthRequest="320" HeightRequest="50" />

Make sure NOTHING interferes with the control. By nothing I mean – overlapping controls, page padding, control margins / spacing, etc. If you have something overlapping the ad control, ads will not display & you won’t receive an error, so be careful.

Next, it’s time to add the custom view renderers; and again, we’ll handle each platform:

Android

Add a new class called AdMobRenderer with the code below. Make sure to keep the ExportRenderer attribute above the namespace, otherwise the magic won’t happen.

[assembly: ExportRenderer(typeof(AdMobView), typeof(AdMobRenderer))]

namespace AdExample.Droid.Renderers
{
    public class AdMobRenderer : ViewRenderer<AdMobView, Android.Gms.Ads.AdView>
    {
        protected override void OnElementChanged(ElementChangedEventArgs<AdMobView> e)
        {
            base.OnElementChanged(e);

            if (Control == null)
            {
                var ad = new Android.Gms.Ads.AdView(Forms.Context);
                ad.AdSize = Android.Gms.Ads.AdSize.Banner;
                ad.AdUnitId = "_your_admob_ad_unit_id_goes_here_";

                var requestbuilder = new Android.Gms.Ads.AdRequest.Builder();
                ad.LoadAd(requestbuilder.Build());

                SetNativeControl(ad);
            }
        }
    }
}

Next, you need to modify your AndroidManifest.xml file to add the AdActivity & required permissions for displaying ads: ACCESS_NETWORK_STATE, INTERNET; just like in the example below.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android">
	<uses-sdk android:minSdkVersion="15" />
	<application>
    <activity android:name="com.google.android.gms.ads.AdActivity" android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize" android:theme="@android:style/Theme.Translucent" />
  </application>
  <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
  <uses-permission android:name="android.permission.INTERNET" />
</manifest>

That’s it. Your Android build should now display ads inside the AdMobView content view.

Windows Phone

Just like for Android, add a new class to your WinPhone project called AdMobRenderer having the code below.

[assembly: ExportRenderer(typeof(AdMobView), typeof(AdMobRenderer))]

namespace AdExample.WinPhone.Renderers
{
    public class AdMobRenderer : ViewRenderer<AdMobView, GoogleAds.AdView>
    {
        protected override void OnElementChanged(ElementChangedEventArgs<AdMobView> e)
        {
            base.OnElementChanged(e);

            if (Control == null)
            {
                var ad = new GoogleAds.AdView();
                ad.Format = AdFormats.Banner;
                ad.AdUnitID = "_your_admob_ad_unit_id_goes_here_";

                var adRequest = new GoogleAds.AdRequest();
                ad.LoadAd(adRequest);

                SetNativeControl(ad);
            }
        }
    }
}

iOS

This, I haven’t got the chance to test yet as I don’t have a Mac around but people say it works, so I’ve added it for reference. Same as before, just add a new class called AdMobRenderer and copy-paste the code below.

[assembly: ExportRenderer(typeof(AdMobView), typeof(AdMobRenderer))]

namespace GazetaSporturilor.iOS.Renderers
{
    public class AdMobRenderer : ViewRenderer
    {
        const string AdmobID = "_your_admob_ad_unit_id_goes_here_";

        GADBannerView adView;
        bool viewOnScreen;

        protected override void OnElementChanged(ElementChangedEventArgs<Xamarin.Forms.View> e)
        {
            base.OnElementChanged(e);

            if (e.NewElement == null)
                return;

            if (e.OldElement == null)
            {
                adView = new GADBannerView(GADAdSizeCons.SmartBannerPortrait)
                {
                    AdUnitID = AdmobID,
                    RootViewController = UIApplication.SharedApplication.Windows[0].RootViewController
                };

                adView.AdReceived += (sender, args) =>
                {
                    if (!viewOnScreen) this.AddSubview(adView);
                    viewOnScreen = true;
                };

                GADRequest request = GADRequest.Request;

                adView.LoadRequest(request);
                base.SetNativeControl(adView);
            }
        }
    }
}

That’s it. Now you have ads being served on all platforms. Any comments or suggestions you have leave them in the comments section below.