more attempts to avoid flicker

collects/mred/private/wx/cocoa/canvas.rkt

@@ -248,6 +248,11 @@
                 (not (send dc can-backing-flush?)))
         (do-on-paint #f #f)))
 
+    (define/public (begin-refresh-sequence)
+      (send dc suspend-flush))
+    (define/public (end-refresh-sequence)
+      (send dc resume-flush))
+
     (define/override (refresh)
       ;; can be called from any thread, including the event-pump thread
       (queue-paint))

collects/mred/private/wx/cocoa/dc.rkt

@@ -57,6 +57,8 @@
        (cairo_surface_destroy s)
        (set! s #f)))))
 
+(define-local-member-name end-delay)
+
 (define dc%
   (class backing-dc%
     (init [(cnvs canvas)])
@@ -94,10 +96,12 @@
     (define/override (resume-flush) 
       (atomically
        (set! suspend-count (sub1 suspend-count))
-       (when (and (zero? suspend-count) req)
+       (super resume-flush)))
-         (cancel-flush-delay req)
+
-         (set! req #f))
+    (define/public (end-delay)
-       (super resume-flush)))))
+      (when (and (zero? suspend-count) req)
+        (cancel-flush-delay req)
+        (set! req #f)))))
 
 (define (do-backing-flush canvas dc ctx dx dy)
   (tellv ctx saveGraphicsState)
@@ -124,4 +128,5 @@
                    (cairo_set_source cr s)
                    (cairo_pattern_destroy s))
                  (cairo_destroy cr))))))
-   (tellv ctx restoreGraphicsState)))
+   (tellv ctx restoreGraphicsState)
+   (send dc end-delay)))

collects/mred/private/wx/cocoa/frame.rkt

@@ -262,15 +262,20 @@
                    "the eventspace hash been shutdown"))
           (when saved-child
             (if (eq? (current-thread) (eventspace-handler-thread es))
-                (send saved-child paint-children)
+                (do-paint-children)
                 (let ([s (make-semaphore)])
                   (queue-callback (lambda ()
-                                    (when saved-child
+                                    (do-paint-children)
-                                      (send saved-child paint-children))
                                     (semaphore-post s)))
-                  (sync/timeout 0.2 s))))))
+                  (sync/timeout 1 s))))))
       (direct-show on?))
 
+    (define/private (do-paint-children)
+      (when saved-child
+        (send saved-child paint-children))
+      (yield-refresh)
+      (try-to-sync-refresh))
+
     (define/public (destroy)
       (when child-sheet (send child-sheet destroy))
       (direct-show #f))

collects/mred/private/wx/cocoa/platform.rkt

@@ -78,8 +78,6 @@
    set-combo-box-font
    get-double-click-time
    run-printout
-   end-refresh-sequence
-   begin-refresh-sequence
    file-creator-and-type
    send-event
    set-executer

collects/mred/private/wx/cocoa/procs.rkt

@@ -30,8 +30,6 @@
  set-executer
  send-event
  file-creator-and-type
- begin-refresh-sequence
- end-refresh-sequence
  run-printout
  get-double-click-time
  set-combo-box-font

collects/mred/private/wx/cocoa/window.rkt

@@ -130,7 +130,7 @@
         (super-tell #:type _void keyDown: event))]
   [-a _void (keyUp: [_id event])
       (unless (do-key-event wxb event self #f)
-        (super-tell #:type _void keyDown: event))]
+        (super-tell #:type _void keyUp: event))]
   [-a _void (insertText: [_NSString str])
       (let ([cit (current-insert-text)])
         (if cit
@@ -455,7 +455,10 @@
       ;; re-sync the display in case a stream of
       ;; events (e.g., key repeat) have a corersponding
       ;; stream of screen updates.
-      (void))
+      (try-to-sync-refresh)
+      (let ([cocoa-win (get-cocoa-window)])
+        (when cocoa-win
+          (tellv cocoa-win flushWindowIfNeeded))))
 
     (define/public (dispatch-on-char/sync e)
       (pre-event-refresh)

collects/mred/private/wx/gtk/canvas.rkt

@@ -373,6 +373,9 @@
 
     (define/public (on-paint) (void))
 
+    (define/public (begin-refresh-sequence) (void))
+    (define/public (end-refresh-sequence) (void))
+
     (define/override (refresh)
       (queue-paint))
 

collects/mred/private/wx/gtk/platform.rkt

@@ -78,8 +78,6 @@
    set-combo-box-font
    get-double-click-time
    run-printout
-   end-refresh-sequence
-   begin-refresh-sequence
    file-creator-and-type
    send-event
    set-executer

collects/mred/private/wx/gtk/procs.rkt

@@ -34,8 +34,6 @@
  set-executer
  send-event
  file-creator-and-type
- begin-refresh-sequence
- end-refresh-sequence
  run-printout
  get-double-click-time
  set-combo-box-font
@@ -84,8 +82,6 @@
   (case-lambda
    [(path cr ty) (void)]
    [(path) (values #"????" #"????")]))
-(define (begin-refresh-sequence) (void))
-(define (end-refresh-sequence) (void))
 (define-unimplemented run-printout)
 (define (get-double-click-time) 250)
 (define (set-combo-box-font f) (void))

collects/mred/private/wx/platform.rkt

@@ -56,8 +56,6 @@
                 set-combo-box-font
                 get-double-click-time
                 run-printout
-                end-refresh-sequence
-                begin-refresh-sequence
                 file-creator-and-type
                 send-event
                 set-executer

collects/mred/private/wx/win32/platform.rkt

@@ -77,8 +77,6 @@
    set-combo-box-font
    get-double-click-time
    run-printout
-   end-refresh-sequence
-   begin-refresh-sequence
    file-creator-and-type
    send-event
    set-executer

collects/mred/private/wx/win32/procs.rkt

@@ -24,8 +24,6 @@
  set-executer
  send-event
  file-creator-and-type
- begin-refresh-sequence
- end-refresh-sequence
  run-printout
  get-double-click-time
  set-combo-box-font
@@ -76,8 +74,6 @@
 (define-unimplemented set-executer)
 (define-unimplemented send-event)
 (define-unimplemented file-creator-and-type)
-(define-unimplemented begin-refresh-sequence)
-(define-unimplemented end-refresh-sequence)
 (define-unimplemented run-printout)
 (define-unimplemented get-double-click-time)
 (define-unimplemented set-combo-box-font)

collects/mred/private/wxme/editor-canvas.rkt

@@ -159,7 +159,9 @@
            get-scroll-range set-scroll-range
            is-shown-to-root?
            show-scrollbars
-	   set-focus)
+	   set-focus
+           begin-refresh-sequence
+           end-refresh-sequence)
 
   (define blink-timer #f)
   (define noloop? #f)

collects/mred/private/wxme/wx.rkt

@@ -42,8 +42,6 @@
          the-clipboard
          the-x-selection-clipboard
          get-double-click-threshold
-         begin-refresh-sequence
-         end-refresh-sequence
          begin-busy-cursor
          end-busy-cursor
          hide-cursor