[plt-scheme] editor behaviour

This is a bug related to `scroll-with-bottom-base', now fixed in SVN.
(For similar reasons, `allow-scroll-to-last' wasn't working right.)


At Mon, 20 Jul 2009 15:10:11 +0200 (CEST), Ivanyi Peter wrote:
> 
>  Robby Findler <robby at eecs.northwestern.edu> írta: 
>  
>  I don't think that there is any (intentional) buffering going on in
>  those methods. Perhaps you could supply a (short) complete program
>  that illustrates the problem? That would be a big help.
>  
> Hi Robby,
> 
> Ok I try to reproduce it. 
> Until then here is another problem with the editor, that
> I had noticed 
> Execute the code below. Press any key in the window
> four times, until the scroll bar is activated. The first
> seven lines disappear and I cannot bring it back.
> This is on Windows XP SP3, PLT-Scheme 4.2.
> 
> Best regards,
> 
> Peter Ivanyi
> 
> ----------------------------------------------------------
> #lang scheme
> 
> (require (lib "class.ss") 
>          (lib "mred.ss" "mred")
>          (lib "framework.ss" "framework") 
> )
> 
> 
> (define (sx-history-entry-new parent)
>   (let*
>     ( (editor (new text%))
>       (canvas (new editor-canvas% (parent parent) 
>                                   (editor editor)
>                                   (style '(control-border))
>               )
>       )
>     )
>     ; we set the tab positions
>     (send editor set-tabs '(100 200 300 400 500 600 700 800 900 1000 100) 1 #t)
>     (send editor lock #t)
>     (send editor hide-caret #t)
>     (send canvas scroll-with-bottom-base #t)
>     canvas
>   )
> )
> 
> (define (sx-history-entry-add window text)
>   (let 
>     ( (ed (send window get-editor)) )
>     (send ed lock #f)
>     (send ed move-position 'end #f 'simple)
>     (send ed insert text)
>     (send ed lock #t)
>   )
> ) 
> 
> 
> (letrec
>   ((sx-history-window%
>      (class frame%
>        (define/override (on-subwindow-char window event)
>          (display "bingo\n")
>          (sx-history-entry-add ed "Hello World\n")
>          #t
>        )
>        (super-instantiate ())
>      )
>    )
>    (win (new sx-history-window% (label "test") (width 200) (height 200)))
>    (ed (sx-history-entry-new win))
>   )
>   (send win show #t)
> )
> 
> 
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