Guide for Xamarin.Google.UserMessagingPlatform?

Question

I am in the final stages of setting up my Android App using Xamarin / C#. I have implemented Google Admob but GDPR rules say that I must have a privacy notice to display ads. Google's documentation says that the Consent SDK is deprecated and that I should use the new User Messaging Platform https://developers.google.com/admob/ump/android/quick-start

I have downloaded the Nuget package Xamarin.Google.UserMessagingPlatform (https://www.nuget.org/packages/Xamarin.Google.UserMessagingPlatform/1.0.0?_src=template) and have imported the libraries but I am struggling to translate Google's code to my project and having searched online there does not appear to be a live documentation link anywhere with examples of implementation in C# / Xamarin. The project site on the package URL 404s and the source repository leads to the general Xamarin repository but I couldn't find a reference to UMP in there.

Is there any documentation available or any examples of the UMP implementation in C#?

Specifically, an example statement I do not know how to handle is this:

new ConsentInformation.OnConsentInfoUpdateSuccessListener() {
            @Override
            public void onConsentInfoUpdateSuccess() {
                // The consent information state was updated.
                // You are now ready to check if a form is available.
            }
        },
        new ConsentInformation.OnConsentInfoUpdateFailureListener() {
            @Override
            public void onConsentInfoUpdateFailure(FormError formError) {
                // Handle the error.
            }

Answer 1

I wrote a full tutorial in my blog if it is useful for you or anyone:

https://supernovaic.blogspot.com/2022/02/guide-for-using-xamaringoogleusermessag.html

Answer 2

In case it's useful, @adamhalperin : In MainActivity.OnCreate, some time after the call to base.OnCreate(bundle); insert this code snippet:

App.LogMessage("DEBUG: MainActivity.OnCreate: Starting consent management flow, via UserMessagingPlatform.");  
            try  
            {  
                ConsentRequestParameters requestParameters = new ConsentRequestParameters  
                    .Builder()  
                    .SetTagForUnderAgeOfConsent(false)  
                    .Build();  
  
                IConsentInformation consentInformation = UserMessagingPlatform.GetConsentInformation(this);  
  
                consentInformation.RequestConsentInfoUpdate(  
                    this,  
                    requestParameters,  
                    new GoogleUMPConsentUpdateSuccessListener(  
                        () =>  
                        {  
                            // The consent information state was updated.  
                            // You are now ready to check if a form is available.  
                            if (consentInformation.IsConsentFormAvailable)  
                            {  
                                UserMessagingPlatform.LoadConsentForm(  
                                    this,  
                                    new GoogleUMPFormLoadSuccessListener((IConsentForm f)=> {  
                                        this.googleUMPConsentForm = f;  
                                        this.googleUMPConsentInformation = consentInformation;  
                                        App.LogMessage("DEBUG: MainActivity.OnCreate: Consent management flow: LoadConsentForm has loaded a form, which will be shown if necessary, once the ViewModel is ready.");  
                                        ViewModel.MainViewModel.OnceViewModelInitialised(DisplayAdvertisingConsentFormIfNecessary);  
                                    }),  
                                    new GoogleUMPFormLoadFailureListener((FormError e)=> {  
                                        // Handle the error.  
                                        App.LogMessage("ERROR: MainActivity.OnCreate: Consent management flow: failed in LoadConsentForm with error " + e.Message);  
                                    }));  
                            }  
                            else  
                            {  
                                App.LogMessage("DEBUG: MainActivity.OnCreate: Consent management flow: RequestConsentInfoUpdate succeeded but no consent form was available.");  
                            }  
                        }),  
                    new GoogleUMPConsentUpdateFailureListener(  
                        (FormError e) =>  
                        {  
                            // Handle the error.  
                            App.LogMessage("ERROR: MainActivity.OnCreate: Consent management flow: failed in RequestConsentInfoUpdate with error " + e.Message);  
                        })  
                    );  
            }  
            catch (Exception ex)  
            {  
                App.LogMessage("ERROR: MainActivity.OnCreate: Exception thrown during consent management flow: ", ex);  
            }  

Then, in the body of the MainActivity class, you will also need to add these definitions:

    private IConsentForm googleUMPConsentForm = null;  
    private IConsentInformation googleUMPConsentInformation = null;  
    public void DisplayAdvertisingConsentFormIfNecessary()  
    {  
        try  
        {  
            if (ViewModel.MainViewModel.Instance.AdvertisingEnabled)  
            {  
                if (googleUMPConsentForm != null && googleUMPConsentInformation != null)  
                {  
                    /* ConsentStatus:  
                        Unknown = 0,  
                        Required = 1,  
                        NotRequired = 2,  
                        Obtained = 3  
                    */  
                    if (googleUMPConsentInformation.ConsentStatus == 1)  
                    {  
                        App.LogMessage("DEBUG: MainActivity.DisplayAdvertisingConsentFormIfNecessary: Consent form is being displayed.");  

                        DisplayAdvertisingConsentForm();  
                    }  
                    else  
                    {  
                        App.LogMessage("DEBUG: MainActivity.DisplayAdvertisingConsentFormIfNecessary: Consent form is not being displayed because consent status is "+ googleUMPConsentInformation.ConsentStatus.ToString());  

                    }  
                }  
                else  
                {  
                    App.LogMessage("ERROR: MainActivity.DisplayAdvertisingConsentFormIfNecessary: consent form or consent information missing.");  
                }  
            }  
        }  
        catch(Exception ex)  
        {  
            App.LogMessage("ERROR: MainActivity.DisplayAdvertisingConsentFormIfNecessary: Exception thrown: ", ex);  
        }  
    }  

    public void DisplayAdvertisingConsentForm()  
    {  
        try  
        {  
            if (ViewModel.MainViewModel.Instance.AdvertisingEnabled)  
            {  
                if (googleUMPConsentForm != null && googleUMPConsentInformation != null)  
                {  
                    App.LogMessage("DEBUG: MainActivity.DisplayAdvertisingConsentForm: Consent form is being displayed.");  

                    Model.DispatcherHelper.CheckBeginInvokeOnUI(() =>  
                    {  
                          
                        googleUMPConsentForm.Show(this, new GoogleUMPConsentFormDismissedListener(  
                            (FormError f) =>  
                            {  
                                if (googleUMPConsentInformation.ConsentStatus == 1) // required  
                                {  
                                    App.LogMessage("ERROR: MainActivity.DisplayAdvertisingConsentForm: Consent was dismissed; showing it again because consent is still required.");  

                                    Model.DispatcherHelper.RunAsyncOnUI(DisplayAdvertisingConsentForm);  
                                }  
                            }));  
                    });  
                }  
                else  
                {  
                    App.LogMessage("ERROR: MainActivity.DisplayAdvertisingConsentForm: consent form or consent information missing.");  
                }  
            }  
        }  
        catch (Exception ex)  
        {  
            App.LogMessage("ERROR: MainActivity.DisplayAdvertisingConsentForm: Exception thrown: ", ex);  
        }  
    }  

    public class GoogleUMPConsentFormDismissedListener : Java.Lang.Object, IConsentFormOnConsentFormDismissedListener  
    {  
        public GoogleUMPConsentFormDismissedListener(Action<FormError> failureAction)  
        {  
            this.a = failureAction;  
        }  
        public void OnConsentFormDismissed(FormError f)  
        {  
            a(f);  
        }  

        private Action<FormError> a = null;  
    }  


    public class GoogleUMPConsentUpdateFailureListener : Java.Lang.Object, IConsentInformationOnConsentInfoUpdateFailureListener  
    {  
        public GoogleUMPConsentUpdateFailureListener(Action<FormError> failureAction)  
        {  
            this.a = failureAction;  
        }  
        public void OnConsentInfoUpdateFailure(FormError f)  
        {  
            a(f);  
        }  

        private Action<FormError> a = null;  
    }  

    public class GoogleUMPConsentUpdateSuccessListener : Java.Lang.Object, IConsentInformationOnConsentInfoUpdateSuccessListener  
    {  
        public GoogleUMPConsentUpdateSuccessListener(Action successAction)  
        {  
            this.a = successAction;  
        }  

        public void OnConsentInfoUpdateSuccess()  
        {  
            a();  
        }  

        private Action a = null;  
    }  

    public class GoogleUMPFormLoadFailureListener : Java.Lang.Object, UserMessagingPlatform.IOnConsentFormLoadFailureListener  
    {  
        public GoogleUMPFormLoadFailureListener(Action<FormError> failureAction)  
        {  
            this.a = failureAction;  
        }  
        public void OnConsentFormLoadFailure(FormError e)  
        {  
            a(e);  
        }  

        private Action<FormError> a = null;  
    }  

    public class GoogleUMPFormLoadSuccessListener : Java.Lang.Object, UserMessagingPlatform.IOnConsentFormLoadSuccessListener  
    {  
        public GoogleUMPFormLoadSuccessListener(Action<IConsentForm> successAction)  
        {  
            this.a = successAction;  
        }  
        public void OnConsentFormLoadSuccess(IConsentForm f)  
        {  
            a(f);  
        }  

        private Action<IConsentForm> a = null;  
    }  

This is just a cut-and-paste of my code - in your case you may need to do something different to replace the call to Model.DispatcherHelper.RunAsyncOnUI/Model.DispatcherHelper.CheckBeginInvokeOnUI (which I use to run something on the UI thread), App.LogMessage which I use to write to the app log, and ViewModel.MainViewModel.Instance.AdvertisingEnabled, which is used to check whether the app is meant to display advertising (it will be false if the user paid to remove advertising)