/// <summary>
/// Initializes an async process to purchas the product. Only one purchase request can be happening at a time
/// </summary>
/// <param name="productId">Product to buy</param>
/// <returns>Purchase object</returns>
public async Task <InAppPurchaseResult> PurchaseAsync(string productId)
{
if (_billingClient == null || !_billingClient.IsReady)
{
throw new InAppPurchaseException(PurchaseError.DeveloperError, "Billing Client is not connected");
}
// Make sure no purchases are being currently made
if (_transactionPurchased != null && !_transactionPurchased.Task.IsCanceled)
{
throw new InAppPurchaseException(PurchaseError.DeveloperError, "Another Purchase is in progress");
}
// First, get the SkuDetail
SkuDetails sku;
if (!_retrievedProducts.TryGetValue(productId, out sku))
{
throw new InAppPurchaseException(PurchaseError.DeveloperError,
$"Cannot find a retrieved Product with {productId} SKU. Products must be first queried from the Play Store");
}
// Build FlowParam for the Purchase
BillingFlowParams flowParams = BillingFlowParams.NewBuilder()
.SetSkuDetails(sku)
.Build();
// Set a new Task Source to wait for completion
_transactionPurchased = new TaskCompletionSource <InAppPurchaseResult>();
Task <InAppPurchaseResult> taskPurchaseComplete = _transactionPurchased.Task;
//_billingClient.QueryPurchaseHistoryAsync(BillingClient.SkuType.Inapp, this);
// Initiate the Billing Process.
BillingResult response = _billingClient.LaunchBillingFlow(_activity, flowParams);
if (response.ResponseCode != BillingResponseCode.Ok)
{
// Reset the in-app-purchase flow
_transactionPurchased?.TrySetCanceled();
_transactionPurchased = null;
throw new InAppPurchaseException(response.ResponseCode.ToPurchaseError(), response.DebugMessage);
}
// Wait till the Task is complete (e.g. Succeeded or Failed - which will result in Exception)
InAppPurchaseResult purchase = await taskPurchaseComplete;
_transactionPurchased = null;
return(purchase);
}
public override void UpdatedTransactions(SKPaymentQueue queue, SKPaymentTransaction[] transactions)
{
Debug.WriteLine("UpdatedTransactions called...");
foreach (SKPaymentTransaction transaction in transactions)
{
if (transaction?.TransactionState == null)
{
break;
}
Debug.WriteLine($"Updated Transaction | {transaction.TransactionState}; ProductId = {transaction.Payment?.ProductIdentifier ?? string.Empty}");
switch (transaction.TransactionState)
{
case SKPaymentTransactionState.Restored:
_restoredTransactions.Add(transaction);
SKPaymentQueue.DefaultQueue.FinishTransaction(transaction);
break;
case SKPaymentTransactionState.Purchased:
InAppPurchaseResult result = transaction.ToInAppPurchase();
// If _transactionPurchased Task is not set, then it means the user initiated the out of the app purchase process
// e.g. purchasing IAP from the App Store
if (_transactionPurchased == null)
{
Debug.WriteLine($"_transactionPurchased is null. Continue with the OnPurchasedOutOfApp call");
InAppPurchaseService.OnPurchasedOutOfApp.Invoke(result);
}
else
{
// Normal Purchase flow when the user clicks purchase button.
Debug.WriteLine($"_transactionPurchased is NOT null. Continue with the normal flow");
_transactionPurchased?.TrySetResult(transaction.ToInAppPurchase());
// Reset the Task
_transactionPurchased = null;
}
SKPaymentQueue.DefaultQueue.FinishTransaction(transaction);
break;
case SKPaymentTransactionState.Failed:
PurchaseError?error = transaction?.Error?.ToPurchaseError();
string description = transaction?.Error?.LocalizedDescription ?? string.Empty;
// Failed Transaction. Set the Exception to the Task, so the caller can react to the issue
_transactionPurchased?.TrySetException(
new InAppPurchaseException(error ?? PurchaseError.GeneralError, description));
// Reset the Task
_transactionPurchased = null;
SKPaymentQueue.DefaultQueue.FinishTransaction(transaction);
break;
case SKPaymentTransactionState.Purchasing:
case SKPaymentTransactionState.Deferred:
default:
break;
}
}
}