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Apollon.WPF/Commands/AsyncCommandBase.cs

@@ -8,13 +8,35 @@ namespace Apollon.WPF.Commands
 {
     public abstract class AsyncCommandBase : CommandBase
     {
+        private bool _isExecuring;
+        public bool IsExecuting
+        {
+            get
+            {
+                return _isExecuring;
+            }
+            set
+            {
+                _isExecuring = value; 
+                OnCanExecutedChanged();
+            }
+        }
+        public override bool CanExecute(object parameter)
+        {
+            return !IsExecuting && base.CanExecute(parameter);
+        }
         public override async void Execute(object parameter)
         {
+            IsExecuting = true;
             try
             {
                 await ExecuteAsync(parameter);
             }
-            catch (Exception) { }                        
+            catch (Exception) { }
+            finally 
+            {
+                IsExecuting = false;
+            }
         }
         public abstract Task ExecuteAsync(object parameter);
     }