This ensures that keybindings for small-step changes
work despite draw-value being FALSE now. This was
fallout from 8ca612c966 that showed up
as arrow keys not working anymore for the color scales
in the color chooser.
According to section 7.1 of WAI-ARIA, the slider role
has the "Children presentational" characteristic, which
indicates that children should not be represented in
the a11y tree, which makes sense, since these are all
just internal gizmos.
This is rarely what you want, so lets turn it off
by default.
Update the one place in our demos where we want to
draw a value, add support for this to gtk-builder-tool,
add a test and mention this change in the migration
guide.
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
Always keep the order:
- [value]
- [marks.top]
- [marks.bottom]
- trough
Which makes sense given the rendering order. Slider should be drawn
after the marks.
Makes it possible to simply remove the custom snapshot implementations
in scale and range. And Adwaita does not depend on the node order
anyway.
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
After the :can-focus change in the previous commit, widgets
need to set suitable focus and grab_focus implementations
to implement the desired focus behavior.
This commit does that for all widgets.
The scale might be allocated at a height greater than requested, and in
that case y=0 is just too far away. Allocate the value directly next to
the slider instead.
Just queue_resize()ing the range itself doesn't work as it will just
re-allocate all the child widgets (i.e. just the trough) to its old
position and size.
There is no reason for this to be a signal, since multiple handlers
don't make sense anyway. It was also broken because the scale needs to
know when a signal handler is added so it can update the value
representation.
Replace the signal with a set_format_value_func function which allows us
to do that.
Fixes#113
It was not copying the terminating \0 in the string, breaking output
in spinbutton (didn't try scale). Fixes#3452.
(cherry picked from commit ae2ef1472c)
