If you run weston with the headless backend, you get a Wayland
display with no seat, which is just fine by the protocol.
gdk_display_get_default_seat() returns NULL in this case. Various
widgets assume that we always have a seat with a keyboard and a
pointer, since that is what X guarantees. Make things survive
without that, so we can run the testsuite under a headless
Wayland compositor.
Add back a property that determines whether an individual
widget will accept focus or not. :can-focus prevents the
focus from ever entering the entire widget hierarchy
below a widget, and :focusable just determines if grabbing
the focus to the widget itself will succeed.
See #2686
This signal is mainly used for bad things, and we
don't want to emit signals during layout if we can
avoid it.
If you are subclassing, you should either use a
layout manager or override the size_allocate vfunc.
If you are using a GtkDrawingArea or GtkGLArea,
use their ::resize signals to learn about size
changes.
Fixes: #2705
The a11y machinery is using signal subscription to get notified of size
changes and notify listeners in turn. This is suboptimal for a couple of
reasons:
- if something connects to the GtkWidget::size-allocate signal we need
to emit it; currently, we have an optimization in place that will
skip the signal emission if there are no handlers, and it would be
nice to go through the fast path
- the accessibility implementation is part of GTK, and should not go
through additional hoops like any out-of-tree API consumer
This is either no chagne because we know for a fact that the returned
value is a GtkNative - after all thats's the type we pass to
gtk_widget_get_ancestor().
Or it is a bug fix since casting NULL to a GtkNative using GTK_NATIVE()
is not going to work, but the API contract of gtk_widget_get_native()
explicitly allows a NULL return value.
We were having a problem where property actions were
not getting state updates because prop_actions_connect
was triggered from some instance_init function while
the widget class is not in place yet.
Delay that call until the widget is fully constructed,
so we can guarantee that we are dealing with the
correct class private struct, and see all class actions.
We already dropped this invariant in gtk_widget_verify_invariants()
because it was not true in all cases. Also, it is not really useful
these days as we extended what it means to be a "child" to also
include widgets in different toplevels.
For example, a popup in a popup button need not be realized just
because the button is in a realized window. The main invariants
we want are:
* Parent is realized before child
* Widget is realized before it is mapped
This sounds like its not a huge deal, but in fact it is a massive win
for things like menus, because when we go between menus in a menubar
each switch between two open menus involves a lot of intermingled
crossing events to different surfaces and for each of these the
tooltip window of the toplevel gets assigned to the new surface. This
shouldn't be a huge deal, as the tooltip window is not even visible,
but due to the realized invariant it get re-realized each time it gets
re-assigned.
This gives us a hook to walk the widget tree whenever a global
setting changes and do per-widget invalidations. This will
replace gtk_style_context_reset_widgets().
This was only living in gtkcontainer.c for historic
reasons. Move it closer to where it belongs, and
rename it from 'idle' to 'layout', since it is
really about the layout phase of the frame clock,
nowadays.
