Re: [Caml-list] lablgtk2 : connecting scroll bar adjustments to a view widget.

[Erik de Castro Lopo <ocaml-erikd@mega-nerd.com>]

Olivier Andrieu wrote:

> Not quite. Apparently this signal is not meant to be connected by
> application code but is used by widget implementations. 

Yes,  Jacques Garrigue explained this on the lablgtk list.

> What you'd need is the gtk_widget_set_scroll_adjustments() function
> (which will emit the set_scroll_adjustments signal you've
> mentionned). Unfortunately this function is not wrapped in lablgtk.

Ah ha.

> All is not lost however, you can still use the GtkScrolledWindow
> convenience widget to implement some "linked scrollbars" setup. You
> simply need to tell the second scrollbar you create to reuse the
> GtkAdjustment object of the first scrollbar. (Untested) Pseudo-code
> follows:
> ,----
> | let pane = GPack.paned `HORIZONTAL ~packing () in
> | 
> | let scroll_win_1 = 
> |   GBin.scrolled_window 
> |     ~packing:pane#add1 () in
> | let scroll_win_2 = 
> |   GBin.scrolled_window
> |     ~vadjustment:scroll_win_1#vadjustment
> |     ~packing:pane#add2 () in
> | 
> | let text_view_1 = GText.view ~packing:scroll_win_1#add () in
> | let text_view_2 = GText.view ~packing:scroll_win_2#add () in
> | ...
> `----
> 
> This is not exactly what you wanted (there are 2 scrollbars) ; you'd
> need gtk_widget_set_scroll_adjustments() for a
> one-scrollbar-two-textviews setup.

Hmm, fortunately I am much more proficient in C than I am in Ocaml
so my best bet is write a widget in C that fits my needs in exactly
and then wrap that in Ocaml.
 
> cf. http://developer.gnome.org/doc/API/2.0/gtk/GtkScrolledWindow.html#desc 
> for a more detailed description of how scrollable widgets are managed.

Thanks again. I'll check it out.

Cheers,
Erik
-- 
+-----------------------------------------------------------+
  Erik de Castro Lopo
+-----------------------------------------------------------+
"Being completely naked during the act of coitus annuls the marriage."
-- Rashad Hassan Khalil, a former dean of Al-Azhar University's 
   faculty of Sharia (or Islamic law)