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
Replace uses of gtk_css_style_get_value with direct access,
throughout the tree. We don't replace all uses, just those
where we are dealing with a fixed property. Be careful to
handle the currentColor special case for color properties.
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.
gtk_snapshot_pop() => removed
gtk_snapshot_pop_and_append() => gtk_snapshot_pop()
So now there is no way to get a rendernode out of the snapshotting API
until you gtk_snapshot_finish().
The following changes were done to (hopefully) achieve backwards
compatibility while allowing themes to change the size of the indicator.
(1) Deprecate the property.
(2) Change the default value of the property to 0. If it is not 0,
use the property's value for the indicator size. This should make
all programs that actually set it keep the size they set it to.
(3) If set to other values than 0, use min-width/min-height of the
check/radio node to size the indicator. This allows themes to change
the size.
(4) Fall back to the previous default size of 16px. This way themes that
do not set the size keep the same behavior.
on:
- GtkToggleButton
- GtkCheckButton
- GtkRadioButton
- GtkModelButton
- GtkCellRendererToggle
- GtkCheckMenuItem
also update themes:
- Adwaita
- Raleigh
but not the win32 theme.
The new :checked state replaces :active for the actual checkedness of
the widgets and :active is now used exclusively while the button is being
pressed.
https://bugzilla.gnome.org/show_bug.cgi?id=733967
Previous commit wrongly identified "active" as containing the new
value. Instead, applications must determine the new value to
update the model with manually based on the value currently in the
model.
Clarify that applications are expected to handle updating the model
from the 'active' property, like GtkCellRendererText does for the
'edited' property.
This fixes a GTK+ 3.0 regression. In GTK+ 2, the render method
on GtkCellRenderer had a expose_area parameter, typically set to
cell_area. This parameter was used for clipping cell content to be
rendered to the cell area (and thus clipping to within the focus
rectangle). During the rendering clean up this parameter was removed
and no clipping put back into place.
Since expose_area was usually equal to cell_area anyway, it does not make
sense to reintroduce the expose_area parameter. Instead, we do clipping at
two levels:
- in gtk_cell_renderer_render() we clip to background_area. We cannot
clip to cell_area here because we want to allow cell renderers to
render in the background area (e.g. background color/effect).
- cell renderers should clip to clip_area when rendering cell
content individually (as they had to individually clip to expose_region
before).
