Merge branch 'dev' of https://github.com/cake-tech/cake_wallet into CW-1529-Improved-Seed-UI

lib/view_model/dashboard/nft_send_view_model.dart

@@ -90,11 +90,25 @@ abstract class NFTSendViewModelBase with Store {
     }
   }
 
-  @action
-  void markSendStarted() => state = IsExecutingState();
+  /// Re-entrancy latch for the send button, held only while the tap handler is
+  /// inside [AuthService.authenticateAction].
+  ///
+  /// Deliberately not [state]: the auth sheet is pushed closable, and closing it
+  /// pops the route without ever invoking onAuthenticationFinished, so a flag
+  /// that waits on the auth result would never be cleared. The caller clears
+  /// this in a finally instead. Once auth succeeds, createTransaction takes over
+  /// the guard by setting IsExecutingState synchronously.
+  bool _isStartingSend = false;
+
+  bool get isStartingSend => _isStartingSend;
+
+  void markSendStarted() => _isStartingSend = true;
+
+  void markSendSettled() => _isStartingSend = false;
 
   @action
   void reset() {
+    _isStartingSend = false;
     pendingTransaction = null;
     state = InitialExecutionState();
   }

lib/view_model/send/send_view_model.dart

@@ -907,9 +907,11 @@ abstract class SendViewModelBase extends WalletChangeListenerViewModel with Stor
       final isSendAll = outputs.any((output) => output.sendAll);
 
       if (!isSendAll) {
-        final estimateTxAmountDouble = outputs.fold<double>(
-            0, (acc, output) => acc + (double.tryParse(output.cryptoAmount) ?? 0));
-        if (estimateTxAmountDouble <= 0) throw Exception('Amount must be greater than 0');
+        final estimateTxAmount = outputs.fold<BigInt>(
+            BigInt.zero, (acc, output) => acc + output.cryptoAmountMoney.amount);
+        if (estimateTxAmount <= BigInt.zero) {
+          throw Exception('Amount must be greater than 0');
+        }
       }
 
       pendingTransaction = await wallet.createTransaction(_credentials(provider));