Adjust project structure

src/Shared/HandyControl_Shared/Interactivity/TriggerCollection.cs

@@ -0,0 +1,42 @@
+using System.Windows;
+
+namespace HandyControl.Interactivity
+{
+    public sealed class TriggerCollection : AttachableCollection<TriggerBase>
+    {
+        internal TriggerCollection()
+        {
+        }
+
+        protected override void OnAttached()
+        {
+            foreach (var triggerBase in this)
+                triggerBase.Attach(AssociatedObject);
+        }
+
+        protected override void OnDetaching()
+        {
+            foreach (var triggerBase in this)
+                triggerBase.Detach();
+        }
+
+        internal override void ItemAdded(TriggerBase item)
+        {
+            if (AssociatedObject == null)
+                return;
+            item.Attach(AssociatedObject);
+        }
+
+        internal override void ItemRemoved(TriggerBase item)
+        {
+            if (((IAttachedObject) item).AssociatedObject == null)
+                return;
+            item.Detach();
+        }
+
+        protected override Freezable CreateInstanceCore()
+        {
+            return new TriggerCollection();
+        }
+    }
+}