Merge pull request #185 from jamesmontemagno/bug/issue-102

Add FinishTransaction to force a FinishTransaction on iOS if things g…

src/Plugin.InAppBilling.Abstractions/BaseInAppBilling.cs

@@ -108,5 +108,9 @@ public virtual void Dispose(bool disposing)
                 disposed = true;
             }
         }
-    }
+
+		public virtual Task<bool> FinishTransaction(InAppBillingPurchase purchase) => Task.FromResult(true);
+
+		public virtual Task<bool> FinishTransaction(string purchaseId) => Task.FromResult(true);
+	}
 }

src/Plugin.InAppBilling.Abstractions/IInAppBilling.cs

@@ -75,5 +75,10 @@ public interface IInAppBilling : IDisposable
         /// <returns>If consumed successful</returns>
         /// <exception cref="InAppBillingPurchaseException">If an error occures during processing</exception>
         Task<InAppBillingPurchase> ConsumePurchaseAsync(string productId, ItemType itemType, string payload, IInAppBillingVerifyPurchase verifyPurchase = null);
-    }
+
+		Task<bool> FinishTransaction(InAppBillingPurchase purchase);
+
+		Task<bool> FinishTransaction(string purchaseId);
+
+	}
 }

src/Plugin.InAppBilling.iOS/InAppBillingImplementation.cs

@@ -90,7 +90,7 @@ Task<IEnumerable<SKProduct>> GetProductAsync(string[] productId)
 
 
 		/// <summary>
-		/// Get all current purhcase for a specifiy product type.
+		/// Get all current purchase for a specifiy product type.
 		/// </summary>
 		/// <param name="itemType">Type of product</param>
 		/// <param name="verifyPurchase">Interface to verify purchase</param>
@@ -310,6 +310,28 @@ Task<SKPaymentTransaction> PurchaseAsync(string productId)
 		public override Task<InAppBillingPurchase> ConsumePurchaseAsync(string productId, ItemType itemType, string payload, IInAppBillingVerifyPurchase verifyPurchase = null) =>
 			null;
 
+		public override Task<bool> FinishTransaction(InAppBillingPurchase purchase) =>
+			FinishTransaction(purchase?.Id);
+
+		public override async Task<bool> FinishTransaction(string purchaseId)
+		{
+			if (string.IsNullOrWhiteSpace(purchaseId))
+				throw new ArgumentException("PurchaseId must be valid", nameof(purchaseId));
+
+			var purchases = await RestoreAsync();
+
+			if (purchases == null)
+				return false;
+
+			var transaction = purchases.Where(p => p.TransactionIdentifier == purchaseId).FirstOrDefault();
+			if (transaction == null)
+				return false;
+
+			SKPaymentQueue.DefaultQueue.FinishTransaction(transaction);
+
+			return true;
+		}
+
 		PaymentObserver paymentObserver;
 
 		static DateTime NSDateToDateTimeUtc(NSDate date)