disable overwrite mode when the overwrite keybindings are disabled

gui-doc/scribblings/framework/text.scrbl

@@ -1,7 +1,6 @@
 #lang scribble/doc
 @(require scribble/manual scribble/extract)
-@(require (for-label framework))
-@(require (for-label scheme/gui))
+@(require (for-label framework racket/gui))
 @title{Text}
 
 @definterface[text:basic<%> (editor:basic<%> text%)]{
@@ -1335,6 +1334,17 @@
   }
 }
 
+@definterface[text:overwrite-disable<%> ()]{
+ Classes implementing this interface disable overwrite mode when
+ the overwrite mode keybindings are turned off.
+}
+
+@defmixin[text:overwrite-disable-mixin (text%) (text:set-overwrite-mode<%>)]{
+ This mixin adds a callback for @racket['framework:overwrite-mode-keybindings]
+ via @racket[preferences:add-callback] that calls @method[text% set-overwrite-mode]
+ with @racket[#f] when the preference is set to @racket[#f].
+}
+
 @defclass[text:basic% (text:basic-mixin (editor:basic-mixin text%)) ()]{}
 @defclass[text:line-spacing% (text:line-spacing-mixin text:basic%) ()]{}
 @defclass[text:hide-caret/selection% (text:hide-caret/selection-mixin text:line-spacing%) ()]{}
@@ -1344,7 +1354,9 @@
 @defclass[text:wide-snip% (text:wide-snip-mixin text:line-spacing%) ()]{}
 @defclass[text:standard-style-list% (editor:standard-style-list-mixin text:wide-snip%) ()]{}
 @defclass[text:input-box% (text:input-box-mixin text:standard-style-list%) ()]{}
-@defclass[text:keymap% (editor:keymap-mixin text:standard-style-list%) ()]{}
+@defclass[text:keymap%
+          (text:overwrite-disable-mixin (editor:keymap-mixin text:standard-style-list%))
+          ()]{}
 @defclass[text:return% (text:return-mixin text:keymap%) ()]{}
 @defclass[text:autowrap% (editor:autowrap-mixin text:keymap%) ()]{}
 @defclass[text:file% (text:file-mixin (editor:file-mixin text:autowrap%)) ()]{}

gui-lib/framework/private/sig.rkt

@@ -200,6 +200,7 @@
      ports<%>
      input-box<%>
      autocomplete<%>
+     overwrite-disable<%>
      
      basic% 
      line-spacing%
@@ -241,7 +242,8 @@
      crlf-line-endings-mixin
      ports-mixin
      input-box-mixin
-     autocomplete-mixin))
+     autocomplete-mixin
+     overwrite-disable-mixin))
   (define-signature text^ extends text-class^
     (autocomplete-append-after
      autocomplete-limit

gui-lib/framework/private/text.rkt

@@ -4549,6 +4549,24 @@ designates the character that triggers autocompletion
          all-string-snips?]))
     
     (super-new)))
+
+(define overwrite-disable<%> (interface ()))
+(define overwrite-disable-mixin
+  (mixin ((class->interface text%)) (overwrite-disable<%>)
+    (inherit set-overwrite-mode)
+    
+    ;; private field held onto by the object
+    ;; because of the weak callback below
+    (define (overwrite-changed-callback p v)
+      (unless v
+        (set-overwrite-mode #f)))
+
+    (preferences:add-callback
+     'framework:overwrite-mode-keybindings
+     overwrite-changed-callback
+     #t)
+     
+    (super-new)))
   
 (define basic% (basic-mixin (editor:basic-mixin text%)))
 (define line-spacing% (line-spacing-mixin basic%))
@@ -4559,7 +4577,7 @@ designates the character that triggers autocompletion
 (define wide-snip% (wide-snip-mixin line-spacing%))
 (define standard-style-list% (editor:standard-style-list-mixin wide-snip%))
 (define input-box% (input-box-mixin standard-style-list%))
-(define -keymap% (editor:keymap-mixin standard-style-list%))
+(define -keymap% (overwrite-disable-mixin (editor:keymap-mixin standard-style-list%)))
 (define return% (return-mixin -keymap%))
 (define autowrap% (editor:autowrap-mixin -keymap%))
 (define file% (file-mixin (editor:file-mixin autowrap%)))