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VM/RelayCommand.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Input;
+
+namespace GroundOrganizer
+{
+    public class RelayCommand : ICommand
+    {
+        private Action<object> execute;
+        private Func<object, bool> canExecute;
+
+        public event EventHandler CanExecuteChanged
+        {
+            add { CommandManager.RequerySuggested += value; }
+            remove { CommandManager.RequerySuggested -= value; }
+        }
+
+        public RelayCommand(Action<object> execute, Func<object, bool> canExecute = null)
+        {
+            this.execute = execute;
+            this.canExecute = canExecute;
+        }
+
+        public bool CanExecute(object parameter)
+        {
+            return this.canExecute == null || this.canExecute(parameter);
+        }
+
+        public void Execute(object parameter)
+        {
+            this.execute(parameter);
+        }
+    }
+}
+