




 
To create a dialog which is window-modal on Cocoa, call the dialog function inside the macro 
with-dialog-results
 as in this example:
(with-dialog-results (symbol okp)
    (prompt-for-symbol
     "Enter a class-name symbol:"
     :ok-check #'(lambda (symbol)
                   (find-class symbol nil)))
  (when okp
    (display-message "symbol is ~S" symbol))
)
On Microsoft Windows, GTK+ and Motif this displays the dialog, calls 
display-message
 when the user clicks 
OK
, and then returns. The effect is no different to what you saw in Prompting for Lisp objects.
On Cocoa, this creates a sheet and returns. 
display-message
 is called when the user clicks 
OK
. The sheet is window-modal, unlike the sheet you saw in Prompting for Lisp objects.
For more details, see the page for 
with-dialog-results
 in the 
LispWorks CAPI Reference Manual
.
CAPI User Guide (Macintosh version) - 30 Aug 2011