Re: [MACTCL] [TCLCORE] Invitation to submit patches for Tk/Cocoa: I need help

[Joe E. <jen...@fl...>]

Kevin  Walzer wrote:
>
> After taking a bit time to consider an approach to these bugs, I have
> decided to revisit the issues by adding to the ttk package (it currently
> lacks a scrollbar for OS X), and also by borrowing from the ttk approach
> for buttons, etc. This will reduce the amount of work relative to
> re-implementing the button and scrollbar code from scratch. When I have
> more to report and /or test, I will post here.


Just a heads-up re: ttk::scrollbars on OSX:

There is an impedance mismatch between the way Tile wants to
implement scrollbars and the HITheme API.  The ttk::scrollbar
Tcl bindings expect scrollbars to be composed of multiple
elements, and use [$sb identify element] to determine what to
do on ButtonPress events &c.  HIThemeDrawTrack(), however,
wants to draw the entire scrollbar as a single unit.

Apple provided hit-test routines to determine what part of the
scrollbar is under a given point [*], but the Tile framework
never evolved a mechanism by which that information could
be queried and returned to scripts.

There were ways to work around this mismatch for sliders
and progress bars, but I never managed to get scrollbars
working; that's why ttk::scrollbar dispatches to tk::scrollbar
on OSX.


--Joe English

  jen...@fl...


[*] If I recall correctly.  It appears that all online documentation
related to the OSX Appearance Manger interface has gone into
the Memory Hole.