in-app billing connection issue - xamarin

Question

I am trying to connect the in-app-billing but the OnConnected event not being hit.
my Android Manifest code is
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="alphaTestApp.alphaTestApp" android:versionCode="1" android:versionName="1.0">
<uses-sdk android:minSdkVersion="15" android:targetSdkVersion="21" />
<uses-permission android:name="com.android.vending.BILLING" />
<uses-permission android:name="android.permission.INTERNET" />
<application android:label="alphaTestApp" android:icon="#drawable/Icon"></application>
</manifest>
And the Main Activity file code is.
[Activity(Label = "alphaTestApp", MainLauncher = true, Icon = "#drawable/icon")]
public class MainActivity : Activity
{
private InAppBillingServiceConnection _serviceConnection;
string publicKey = "REDACTED";
private IList<Product> _products;
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
SetContentView(Resource.Layout.Main);
_serviceConnection = new InAppBillingServiceConnection(this, publicKey);
if (_serviceConnection == null)
{
Toast t = Toast.MakeText(this, "Error while connecting", ToastLength.Long);
t.Show();
}
_serviceConnection.Connect();
Toast t1 = Toast.MakeText(this, "Connected app", ToastLength.Long);
t1.Show();
_serviceConnection.OnConnected += () =>
{
Toast t2 = Toast.MakeText(this, "Retrieving Items", ToastLength.Long);
t2.Show();
_products = _serviceConnection.BillingHandler.QueryInventoryAsync(new List<string> {
"goldcoin100"
}, ItemType.Product) as IList<Product>;
if (_products == null)
return;
_serviceConnection.BillingHandler.BuyProduct(_products[0]);
};
Button button = FindViewById<Button>(Resource.Id.MyButton);
button.Click += delegate
{
Toast t3 = Toast.MakeText(this, "Retrieving Items", ToastLength.Long);
t3.Show();
_products = _serviceConnection.BillingHandler.QueryInventoryAsync(new List<string> {
"goldcoin100"
}, ItemType.Product) as IList<Product>;
if (_products == null)
return;
_serviceConnection.BillingHandler.BuyProduct(_products[0]);
};
}
}

Answer 1

It's probably not the reason, but it would be best to set your OnConnected handler before you call Connect just in case it connects in less time than it takes for the Toast code to run.
Also, you should make the OnConnected handler async and then await on the call to QueryInventoryAsync (in a Lambda the async keyword goes before the brackets, e.g. OnConnected += async () => ...). As it is, QueryInventoryAsync will return a Task<IList<Product>> so trying to convert it using as IList<Product> will fail and _products will always be null.
If you're running on an emulator, make sure that you've got Google Play Services installed and up-to-date. There's an article on doing this for the Xamarin Android Player here: Installing Google Play Services in XAP. Although note that BuyProduct shouldn't work on an emulator using real products, you'll need to use the test product IDs (e.g. ReservedTestProductIDs.Purchased, and note that once you've purchased this one you'll need to call ConsumePurchase on it before you can purchase it again).
Also, don't post your API key on an open forum.