From 81e5a24390b06ec8f3d67272c7e284d37a18f3f2 Mon Sep 17 00:00:00 2001
From: Robby Findler <robby@racket-lang.org>
Date: Thu, 18 Oct 2007 22:12:59 +0000
Subject: [PATCH] fix to PR 8900

svn: r7526
---
 collects/framework/preferences.ss         |  1 -
 collects/framework/private/preferences.ss | 18 +++++++++++-------
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/collects/framework/preferences.ss b/collects/framework/preferences.ss
index 9099202236..457f2d7866 100644
--- a/collects/framework/preferences.ss
+++ b/collects/framework/preferences.ss
@@ -156,7 +156,6 @@ the state transitions / contracts are:
            p
            value)]))
      ps values)
-    
     ((preferences:low-level-put-preferences)
      (map add-pref-prefix ps) 
      (map (λ (p value) (marshall-pref p value))
diff --git a/collects/framework/private/preferences.ss b/collects/framework/private/preferences.ss
index 64dba5f28f..c06af3a3f2 100644
--- a/collects/framework/private/preferences.ss
+++ b/collects/framework/private/preferences.ss
@@ -185,7 +185,7 @@ the state transitions / contracts are:
   
   (define (hide-dialog)
     (when preferences-dialog
-      (send preferences-dialog show #f)))
+      (send preferences-dialog close)))
   
   (define (show-dialog)
     (if preferences-dialog
@@ -207,18 +207,23 @@ the state transitions / contracts are:
   
   (define (make-preferences-dialog)
     (letrec ([stashed-prefs (preferences:get-prefs-snapshot)]
+             [cancelled? #t]
              [frame-stashed-prefs%
               (class frame:basic%
+                (inherit close)
                 (define/override (on-subwindow-char receiver event)
                   (cond
                     [(eq? 'escape (send event get-key-code))
-                     (cancel-callback)]
+                     (close)]
                     [else 
                      (super on-subwindow-char receiver event)]))
                 (define/augment (on-close)
-                  (cancel-callback))
+                  (when cancelled?
+                    (preferences:restore-prefs-snapshot stashed-prefs)))
                 (define/override (show on?)
                   (when on?
+                    ;; reset the flag and save new prefs when the window becomes visible
+                    (set! cancelled? #t)
                     (set! stashed-prefs (preferences:get-prefs-snapshot)))
                   (super show on?))
                 (super-new))]
@@ -275,10 +280,9 @@ the state transitions / contracts are:
                               (for-each
                                (λ (f) (f))
                                on-close-dialog-callbacks)
-                              (hide-dialog)))]
-             [cancel-callback (λ ()
-                                (hide-dialog)
-                                (preferences:restore-prefs-snapshot stashed-prefs))])
+                              (set! cancelled? #f)
+                              (send frame close)))]
+             [cancel-callback (λ () (send frame close))])
       (new button%
            [label (string-constant revert-to-defaults)]
            [callback