




 
Any toolbar object may be disabled, by setting its 
enabled
 slot to 
nil
. Disabling a toolbar or toolbar component prevents the user from interacting with any buttons contained in it.
All toolbar objects may also have an 
enabled-function
 specified. This is called whenever update-toolbar is called. If it returns 
t
, the toolbar object will be enabled; if it returns 
nil
, the object will be disabled.