Add RMB and MMB actions to Type Editor control

Source/Editor/CustomEditors/Editors/TypeEditor.cs

@@ -32,7 +32,7 @@ namespace FlaxEditor.CustomEditors.Editors
         private DragHandlers _dragHandlers;
 
         /// <summary>
-        /// Gets or sets the allowed type (given type and all sub classes). Must be <see cref="System.Type"/> type of any subclass.
+        /// Gets or sets the allowed type (given type and all subclasses). Must be <see cref="System.Type"/> type of any subclass.
         /// </summary>
         public ScriptType Type
         {
@@ -209,7 +209,6 @@ namespace FlaxEditor.CustomEditors.Editors
         /// <inheritdoc />
         public override bool OnMouseUp(Float2 location, MouseButton button)
         {
-            // Cache data
             bool isSelected = _value != ScriptType.Null;
             var frameRect = new Rectangle(0, 0, Width - 16, 16);
             if (isSelected && _type == ScriptType.Null)
@@ -220,11 +219,30 @@ namespace FlaxEditor.CustomEditors.Editors
 
             // Deselect
             if (_value && button1Rect.Contains(ref location) && _type == ScriptType.Null)
+            {
+                Focus();
                 Value = ScriptType.Null;
+                return true;
+            }
 
             // Picker dropdown menu
             if ((isSelected && _type == ScriptType.Null ? button2Rect : button1Rect).Contains(ref location))
+            {
                 ShowDropDownMenu();
+                return true;
+            }
+
+            // Clear value with MMB or show picker with RMB
+            if (button == MouseButton.Middle)
+            {
+                Focus();
+                Value = ScriptType.Null;
+                return true;
+            }
+            if (button == MouseButton.Right)
+            {
+                ShowDropDownMenu();
+            }
 
             return base.OnMouseUp(location, button);
         }