--- a/VisualComponent.st	Fri Feb 10 11:24:25 2017 +0100
+++ b/VisualComponent.st	Fri Feb 10 11:38:14 2017 +0100
@@ -81,6 +81,14 @@
     ^ SimpleView defaultViewBackgroundColor
 
     "Created: / 18.6.1998 / 16:15:17 / cg"
+!
+
+isAbstract
+    "Return if this class is an abstract class.
+     True is returned here for myself only; false for subclasses.
+     Abstract subclasses must redefine this again."
+
+    ^ self == VisualComponent.
 ! !
 
 !VisualComponent methodsFor:'accessing'!