To build a better world sometimes means having to tear the old one down.
-- Alexander Pierce, "Captain America: The Winter Soldier"
ATK served us well for nearly 20 years, but the world has changed, and
GTK has changed with it. Now ATK is mostly a hindrance towards improving
the accessibility stack:
- it maps to a very specific implementation, AT-SPI, which is Linux and
Unix specific
- it requires implementing the same functionality in three different
layers of the stack: AT-SPI, ATK, and GTK
- only GTK uses it; every other Linux and Unix toolkit and application
talks to AT-SPI directly, including assistive technologies
Sadly, we cannot incrementally port GTK to a new accessibility stack;
since ATK insulates us entirely from the underlying implementation, we
cannot replace it piecemeal. Instead, we're going to remove everything
and then incrementally build on a clean slate:
- add an "accessible" interface, implemented by GTK objects directly,
which describe the accessible role and state changes for every UI
element
- add an "assistive technology context" to proxy a native accessibility
API, and assign it to every widget
- implement the AT context depending on the platform
For more information, see: https://gitlab.gnome.org/GNOME/gtk/-/issues/2833
We only want to send grab-notify to widgets that might have been
interacting with devices via events. Instead of going through all
widgets in all toplevels, we have the window/pointer focus information,
so we can just traverse the widget stacks for every involved foci.
This got stuck in ancient times when widgets were windowed, so the devices
in a window to know the devices in that widget would pan out. We do only
want here the devices that are inside the widget, not spread over the
surface, so rewrite this helper function to poke the toplevel foci, and
look they are contained inside the widget.
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.
The previous code was unreffing the window twice, which caused problems
during dialog destruction. Move to g_list_store_find instead of
iterating manually.
ref() the window before and unref() after. g_list_store_remove will
actually unref() the window, since the toplevel_list owns its own
reference.
Fixes#2741Fixes#2742
I thought I could get away with just unrealizing the
window, but it turns out that gtk_window_hide() is the
place where we remove grabs when a modal dialog goes
away, so we ended up with stuck grabs.
Don't call gtk_widget_destroy; instead implement
gtk_window_destroy outselves by removing the window
from the toplevel lista and dropping the reference that
GTK holds.
