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
Remove all the old 2.x and 3.x version annotations.
GTK+ 4 is a new start, and from the perspective of a
GTK+ 4 developer all these APIs have been around since
the beginning.
This patch makes that work using 1 of 2 options:
1. Add all missing enums to the switch statement
or
2. Cast the switch argument to a uint to avoid having to do that (mostly
for GdkEventType).
I even found a bug while doing that: clearing a GtkImage with a surface
did not notify thae surface property.
The reason for enabling this flag even though it is tedious at times is
that it is very useful when adding values to an enum, because it makes
GTK immediately warn about all the switch statements where this enum is
relevant.
And I expect changes to enums to be frequent during the GTK4 development
cycle.
gtk_tree_selection_real_modify_range() has a g_return_if_fail() if the
start or end paths passed to it do not correspond to real tree nodes.
However, GtkTreePaths inherently do not have to be valid, so it should
be acceptable to call gtk_tree_selection_select_range() with
non-existent paths. Replace the g_return_if_fail() by a silent return,
and add a unit test.
https://bugzilla.gnome.org/show_bug.cgi?id=712760
_gtk_rbtree_first() can potentially return NULL if the RB tree is empty,
which would result in NULL pointer dereferences in the GtkTreeSelection
code. Gracefully handle them.
Found by scan-build.
https://bugzilla.gnome.org/show_bug.cgi?id=712760
This commit exposes the get_type() functions and standard
headers for accessible implementations. This makes it possible
to derive from the GTK accessible implementations without
GType magic tricks. This is necessary, because we require the
a11y type hierarchy to be parallel to the widget type hierarchy.
So, if you derive a widget and need to adjust its a11y implementation,
you have to be able to derive its accessible implementation.
This commit probably exposes more than is absolutely necessary,
it also exposes accessibles of widgets that are unlikely candidates
for deriving from.
_gtk_tree_view_find_path() was not a name that not really described what
the function does. And I kept forgetting it. Also, it took the tree view
as an argument and that was completely unnecessary.
The Gtk-custom.c file in gir-repository contained a number of
introspection annotations. Merge those into the GTK source files.
Some documentation was moved from the tmpl/ files to accomodate
the addition of annotations.
