Changed events in VisualScripting relating things to weak references

src/Artemis.VisualScripting/Events/PinConnectedEventManager.cs

@@ -0,0 +1,77 @@
+using System;
+using System.Windows;
+using Artemis.Core;
+using Artemis.Core.Events;
+
+namespace Artemis.VisualScripting.Events
+{
+    public class PinConnectedEventManager : WeakEventManager
+    {
+        #region Properties & Fields
+
+        private static PinConnectedEventManager CurrentManager
+        {
+            get
+            {
+                Type type = typeof(PinConnectedEventManager);
+                PinConnectedEventManager changedEventManager = (PinConnectedEventManager)GetCurrentManager(type);
+                if (changedEventManager == null)
+                {
+                    changedEventManager = new PinConnectedEventManager();
+                    SetCurrentManager(type, changedEventManager);
+                }
+                return changedEventManager;
+            }
+        }
+
+        #endregion
+
+        #region Constructors
+
+        private PinConnectedEventManager()
+        { }
+
+        #endregion
+
+        #region Methods
+
+        public static void AddListener(IPin source, IWeakEventListener listener)
+        {
+            if (source == null) throw new ArgumentNullException(nameof(source));
+            if (listener == null) throw new ArgumentNullException(nameof(listener));
+
+            CurrentManager.ProtectedAddListener(source, listener);
+        }
+
+        public static void RemoveListener(IPin source, IWeakEventListener listener)
+        {
+            if (listener == null) throw new ArgumentNullException(nameof(listener));
+
+            CurrentManager.ProtectedRemoveListener(source, listener);
+        }
+
+        public static void AddHandler(IPin source, EventHandler<SingleValueEventArgs<IPin>> handler)
+        {
+            if (handler == null) throw new ArgumentNullException(nameof(handler));
+
+            CurrentManager.ProtectedAddHandler(source, handler);
+        }
+
+        public static void RemoveHandler(IPin source, EventHandler<SingleValueEventArgs<IPin>> handler)
+        {
+            if (handler == null) throw new ArgumentNullException(nameof(handler));
+
+            CurrentManager.ProtectedRemoveHandler(source, handler);
+        }
+
+        protected override ListenerList NewListenerList() => new ListenerList<SingleValueEventArgs<IPin>>();
+
+        protected override void StartListening(object source) => ((IPin)source).PinConnected += OnPinConnected;
+
+        protected override void StopListening(object source) => ((IPin)source).PinConnected -= OnPinConnected;
+
+        private void OnPinConnected(object sender, SingleValueEventArgs<IPin> args) => DeliverEvent(sender, args);
+
+        #endregion
+    }
+}