--- a/ButtonController.st	Fri Jan 24 15:32:29 1997 +0100
+++ b/ButtonController.st	Fri Jan 24 15:39:40 1997 +0100
@@ -44,6 +44,31 @@
     access to the controllers behavior is possible via messages to the button.
     (setting actions, controlling autorepeat etc.)
 
+    A ButtonController supports 3 types of notifications:
+        MVC change notification - as usual
+        channel notifications   - through the pressChannel/releaseChannels
+        action callBack         - through pressAction / releaseAction blocks.
+
+    Notifications are made in the above order (i.e. an actionBlock sees the model
+    already changed, if there is a model).
+
+    Having multiple mechanisms here is both historic and to make the life
+    of simple applications easier - most buttons dont need a model or notification
+    channels and simply perform some action.
+    In general: actionBlocks are useful, if there is a single subject which
+    needs to be told about the press (i.e. actionButtons); 
+    models should be used when the button represents some value in some other
+    object.
+    Channels are much like the MVC approach, however, these are useful if
+    press/release/label etc. may come from different objects, and a single 
+    (synthetic) model does not make sense or is not appropriate.
+
+    Actually, the channels are the most general - and the other mechanism could
+    (and will, maybe) based upon them; after all, an actionBlock is a channel,
+    whcih sends #value to its block ....
+
+
+
     See examples in the Button class.
 
     [Instance variables:]
@@ -604,5 +629,5 @@
 !ButtonController class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libwidg/ButtonController.st,v 1.36 1997-01-24 14:32:29 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libwidg/ButtonController.st,v 1.37 1997-01-24 14:39:40 cg Exp $'
 ! !