Re: Needing GtkScrollbar and GtkViewport to expose value changes

[Owen Taylor <otaylor redhat com>]

Brian Cameron <Brian Cameron sun com> writes:

> Gtk Experts:
> 
> A quick question.  The ATK requires that the GtkViewport and the
> GtkScrollbar support notification when their values change (e.g.
> the slider or viewport is moved, etc.)
> 
> I took a look at the code, and it seems that GtkViewport
> generates a "set-scroll-adjustments" signal and has the following
> properties PROP_HADJUSTMENT, PROP_VADJUSTMENT, and PROP_SHADOW_TYPE.
> The code isn't completely clear to me and I was wondering if these
> expose value changes.
> 
> Looking at the GtkScrollbar, GtkHScrollbar, and GtkVScrollbar it
> doesn't look like they generate any signals.  It looks like GtkScrollbar
> exposes min_slider_length, fixed_slider_length, has_backward_stepper,
> has_forward_stepper, has_secondary_backward_stepper, and 
> has_secondary_forward_stepper.  Again this code isn't clear to me
> and I'm also wondering if these expose value changes.
> 
> Any help would be appreicated. 

Notification on scrolbars is done with the ::value_changed 
(and ::changed for changes in upper/lower/etc) signals on
range->adjustment.

"set-scroll-adjustments" is an interface masquerading as a signal
[ crude hack from GTK+-1.2 ] and should be ignored.

Regard,s
                                        Owen