Converting InAppBilling.Plugin to Amazon

Hello Guys,

I have create a Android application in Xamarin and i would like to also have in on Amazon store.

It uses in App purchases

Currently im implementing those purchases with this code:

public async Task<bool> WasItemPurchased(string productId)
{
var billing = CrossInAppBilling.Current;
var result = false;
try
{
var connected = await billing.ConnectAsync(ItemType.InAppPurchase);
if (!connected)
{
//Couldn't connect
return false;
}
//check purchases
var verify = new InAppBillingVerify();
var purchases = await billing.GetPurchasesAsync(ItemType.InAppPurchase, verify);
//check for null just incase
if (purchases?.Any(p => p.ProductId == productId) ?? false)
{
//Purchase restored
Preferences.Set(productId, true);
return true;
}
else
{
//no purchases found
//Toast.MakeText(this, GetString(Resource.String.Options_RestoreUnavailable), ToastLength.Long);
return false;
}
}
catch (InAppBillingPurchaseException purchaseEx)
{
var message = string.Empty;
switch (purchaseEx.PurchaseError)
{
case PurchaseError.AppStoreUnavailable:
RestorePurchasesStatusMessage = GetString(Resource.String.Options_PaidFunctions_ErrorAppStoreUnavailable);
break;
case PurchaseError.BillingUnavailable:
RestorePurchasesStatusMessage = GetString(Resource.String.Options_PaidFunctions_ErrorBillingUnavailable);
break;
case PurchaseError.PaymentInvalid:
RestorePurchasesStatusMessage = GetString(Resource.String.Options_PaidFunctions_ErrorPaymentInvalid);
break;
case PurchaseError.PaymentNotAllowed:
RestorePurchasesStatusMessage = GetString(Resource.String.Options_PaidFunctions_ErrorPaymentNotAllowed);
break;
case PurchaseError.AlreadyOwned:
RestorePurchasesStatusMessage = GetString(Resource.String.Options_PaidFunctions_ErrorAlreadyOwned);
Preferences.Set(productId, true);
result = true;
break;
}
//Decide if it is an error we care about
if (string.IsNullOrWhiteSpace(message))
return false;
//Display message to user
//Toast.MakeText(this, message, ToastLength.Long);
}
catch (Exception exception)
{
Crashes.TrackError(exception);
//Something has gone wrong
RestorePurchasesStatusMessage = GetString(Resource.String.Options_PaidFunctions_ErrorAppStoreUnavailable);
//Toast.MakeText(this, GetString(Resource.String.Options_PaidFunctions_ErrorAppStoreUnavailable), ToastLength.Long);
}
finally
{
await billing.DisconnectAsync();
}
return result;
}
public async Task<bool> PurchaseItem(string productId, string payload)
{
var billing = CrossInAppBilling.Current;
try
{
var connected = await billing.ConnectAsync(ItemType.InAppPurchase);
if (!connected)
{
//we are offline or can't connect, don't try to purchase
return false;
}
//check purchases
var verify = new InAppBillingVerify();
var purchase = await billing.PurchaseAsync(productId, ItemType.InAppPurchase, payload, verify);
//possibility that a null came through.
if (purchase == null)
{
//did not purchase
}
else if (purchase.State == PurchaseState.Purchased)
{
//purchased!
Preferences.Set(productId, true);
}
}
catch (InAppBillingPurchaseException purchaseEx)
{
var message = string.Empty;
switch (purchaseEx.PurchaseError)
{
case PurchaseError.AppStoreUnavailable:
message = GetString(Resource.String.Options_PaidFunctions_ErrorAppStoreUnavailable);
break;
case PurchaseError.BillingUnavailable:
message = GetString(Resource.String.Options_PaidFunctions_ErrorBillingUnavailable);
break;
case PurchaseError.PaymentInvalid:
message = GetString(Resource.String.Options_PaidFunctions_ErrorPaymentInvalid);
break;
case PurchaseError.PaymentNotAllowed:
message = GetString(Resource.String.Options_PaidFunctions_ErrorPaymentNotAllowed);
break;
case PurchaseError.AlreadyOwned:
message = GetString(Resource.String.Options_PaidFunctions_ErrorAlreadyOwned);
Preferences.Set(productId, true);
EnableOrDisableProFeatures();
break;
}
//Decide if it is an error we care about
if (string.IsNullOrWhiteSpace(message))
return false;
//Display message to user
DisplayToast(message, ToastLength.Long);
}
catch (Exception exception)
{
Crashes.TrackError(exception);
//Something else has gone wrong, log it
//Debug("Issue connecting: " + ex);
DisplayToast(GetString(Resource.String.Options_PaidFunctions_ErrorAppStoreUnavailable), ToastLength.Long);
}
finally
{
await billing.DisconnectAsync();
}
return false;
}
private async Task RestorePurchases()
{
var currentConnectivity = Connectivity.NetworkAccess;
var restorePurchasesResults = new List<bool>();
if (currentConnectivity == NetworkAccess.Internet)
{
restorePurchasesResults.Add(await WasItemPurchased(GetString(Resource.String.Options_PaidFunctions_PurchaseTemplatesAndMoreButtons)));
restorePurchasesResults.Add(await WasItemPurchased(GetString(Resource.String.Options_PaidFunctions_PurchaseCustomResources)));
restorePurchasesResults.Add(await WasItemPurchased(GetString(Resource.String.Options_PaidFunctions_PurchaseDisplayWebpageAfterVote)));
if (restorePurchasesResults.Contains(true))
{
DisplayToast(GetString(Resource.String.Options_PaidFunctions_PurchasesRestored), ToastLength.Long);
EnableOrDisableProFeatures();
}
else
{
if (string.IsNullOrEmpty(RestorePurchasesStatusMessage))
RestorePurchasesStatusMessage = GetString(Resource.String.Options_PaidFunctions_PurchasesNotFound);
DisplayToast(RestorePurchasesStatusMessage, ToastLength.Long);
}
}
else
{
DisplayToast(GetString(Resource.String.Options_InternetUnavailable), ToastLength.Long);
}
}
private async Task<string> GetProductPrice(string productId)
{
var billing = CrossInAppBilling.Current;
try
{
var connected = await billing.ConnectAsync(ItemType.InAppPurchase);
if (!connected)
{
//Couldn't connect
return string.Empty;
}
//check purchases
var item = await billing.GetProductInfoAsync(ItemType.InAppPurchase, productId);
if (item != null)
return item.ToList()[0].LocalizedPrice;
}
catch (InAppBillingPurchaseException purchaseEx)
{
var message = string.Empty;
switch (purchaseEx.PurchaseError)
{
case PurchaseError.AppStoreUnavailable:
message = GetString(Resource.String.Options_PaidFunctions_ErrorAppStoreUnavailable);
break;
case PurchaseError.BillingUnavailable:
message = GetString(Resource.String.Options_PaidFunctions_ErrorBillingUnavailable);
break;
case PurchaseError.PaymentInvalid:
message = GetString(Resource.String.Options_PaidFunctions_ErrorPaymentInvalid);
break;
case PurchaseError.PaymentNotAllowed:
message = GetString(Resource.String.Options_PaidFunctions_ErrorPaymentNotAllowed);
break;
}
//Decide if it is an error we care about
if (string.IsNullOrWhiteSpace(message))
return string.Empty;
//Display message to user
DisplayToast(message, ToastLength.Long);
}
catch (Exception exception)
{
Crashes.TrackError(exception);
//Something has gone wrong
}
finally
{
await billing.DisconnectAsync();
}
return string.Empty;
}

And i have to do similar function for the Amazon store like the API details here:

https://developer.amazon.com/docs/cross-platform-plugins/cpp-use-the-iap-plugin-for-xamarin.html

However i dont even know where to start to convert those functions, Amazon API confuse me, can someone help me?

1 Reply

Know the answer? Post it — somebody with the same question will find it here.

Mario Scheeren6y ago
All methods you need are described here :

https://developer.amazon.com/de/docs/cross-platform-plugins/cpp-use-the-iap-plugin-for-xamarin.html

Get Userdata, get Information about the SKU and Purchse an SKU .... so what is it that confuses you?

It's an async scenario where you have to basically do this:

Create an

IAmazonIapV2 iapService = AmazonIapV2Impl.Instance;

probably you want to reuse it ...

Add / create Eventhandlers for each method like

iapService.AddGetProductDataResponseListener(EventHandler);
iapService.AddGetPurchaseUpdatesResponseListener(EventHandler);
... etc

Then fire the request you want, save yout reQuestID for further mapping,

string requestIdString = response.RequestId

and wait for the eventhandler to kick in ...

Now determine for which request (RequestID) you get the answer for.