Re: gtk_widget_grab_focus sets scrollbar adjustments to 0

[Franco Broi <franco bordernet com au>]

On Mon, 2015-12-28 at 19:26 +0900, Tristan Van Berkom wrote:
> On Mon, 2015-12-28 at 18:01 +0800, Franco Broi wrote:
> > Hi
> >
> > I have a drawingarea inside a scrolled window for which I'd like to
> > grab
> > the focus so the user can use keyboard inputs but I want to do it
> > without changing the scrolled window position. What I'm finding is
> > the
> > gtk_widget_grab_focus call on the drawable results in the scrolled
> > window adjustments being set to zero.
> [...]
>
> > I can see the code in gtk_container_real_set_focus_child calling
> > gtk_adjustment_clamp_page but don't understand why and I don't see
> > any
> > way to stop it from doing it.
> [...]
>
> Hi,
>    the reasoning is that usually focus is not given to the direct child
> of a scrolled window, but to another grandchild.
>
> This usually makes sense so that when using keynav and tabbing from
> widget to widget inside a scrolled area, the scrolled window will
> automatically adjust itself to reveal the new button/entry/widget which
> may otherwise be hidden (so the user doesnt end up having to manually
> move the scrollbars to see what widget is focused).
>
> For your case, you should be able to opt out by simply clearing the
> focus adjustments with the gtk_container_set_focus_[v/h]adjustment()
> APIs.

Thanks for the quick reply Tristan. Had me flummoxed for a while until I
worked out that it is the adjustments of the scrolledwindow's child that
need to be cleared - the viewport??

gtk_container_set_focus_vadjustment(GTK_CONTAINER(gtk_bin_get_child(GTK_BIN(sw))), NULL);

Cheers,