There's probably an expectation from the app developers that
Ctrl+F or similar common shortcuts for starting a search will
be handled by the widget, when this is not the case. Explicitely
mention it in the docs to avoid confusion.
https://bugzilla.gnome.org/show_bug.cgi?id=701523
We already take care to not track headers when the listbox is hidden,
because that can be very expensive during creation, so we might as
well skip reseparate() too. The only time we don't want to skip it
is when we're about to show the list.
This was added from https://bugzilla.gnome.org/show_bug.cgi?id=691979
where it was wanted in order to get a "all children filtered" kind
of row. However, the solution is not really generic enough, because
filtering can happen for other reasons than a full refilter (i.e. due
to a row change), and the partial fix you can get by counting children
after refilter can be achieved by manually doing it whenever you manually
called refilter anyway.
Its possible we should have some better solution for the "empty state"
though.
Historically the following states propagated to children:
GTK_STATE_FLAG_ACTIVE
GTK_STATE_FLAG_PRELIGHT
GTK_STATE_FLAG_SELECTED
GTK_STATE_FLAG_INSENSITIVE
GTK_STATE_FLAG_INCONSISTENT
GTK_STATE_FLAG_BACKDROP
However, several of these are problematic on containers like GtkListBox.
For instance, if a row is ACTIVE or SELECTED then all children (like e.g
a button) inside the row will *also* look active/selected. This is almost
never right. The right way to theme this is to catch e.g. SELECTED on the
container itself and set e.g. the color and let the children inherit
the color instead of the flag.
We now propagate only these flags:
GTK_STATE_FLAG_INSENSITIVE
GTK_STATE_FLAG_BACKDROP
Which make sense to be recursive as they really affect every widget
inside the container.
However, this is a CSS theme break, and while most things continue working
as-is some themes may need minor tweaks.
Now that we automatically set up the focus_vadjustment we only
need the adjustment to handle the page-up/down scroll length correctly.
We use parent_set to automatically pick up the adjustment from a
scrollable (i.e. viewport) parent which makes add_to_scrolled useless, so
it can be removed.
When adding with a viewport we automatically set the focus
adjustments on the viewport from the scrolled window, so that
when any child widget gets focused we automatically scroll to it.
This is generally nice, but its particularly important for GtkListBox
where focus changing is how we navigate between rows.
We also ensure that the adjustments are always set before adding the
child to the viewport, which we will need later to pick up the
adjustments on add.
