Unparent the child widget before tearing down its
stack page. This is necessary so a11y can still access
the stack page accessible to emit change notification
when it learns that the child is removed.
Since we mention abstract roles in the documentation
for GtkAccessibleRole, we should say what roles are
abstract. Doing this shows that we actually use two
abstract roles heavily, ourselves: WIDGET and WINDOW.
GtkModelButton is no longer derived from GtkButton,
but can still treat it like a button for the purposes
of having a click action. This lets ATs activate
menu items again.
When the button role changes, we want to update the
accessible role to match. Since accessible roles are
unchangeable post-creation of the AT context, we have
to cheat a bit and recreate the whole context.
Set the accessible role to GTK_ACCESSIBLE_ROLE_MENU_ITEM.
This is incomplete, we need to recreate the context when
the buttons role changes, and there are other things that
need to be set.
According to section 7.1 of WAI-ARIA, the progressbar role
has the "Children presentational" characteristic, which
indicates that children should not be represented in
the a11y tree.
According to section 7.1 of WAI-ARIA, the meter role
has the "Children presentational" characteristic, which
indicates that children should not be represented in
the a11y tree.
According to section 7.1 of WAI-ARIA, the switch role
has the "Children presentational" characteristic, which
indicates that children should not be represented in
the a11y tree.
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.
Recompute the layout when the css style change
affects text attributes. This matches what we do
in GtkLabel, and without this, changing the
font-features-setting css property in the Inspector
does not have immediate effect.
The last event, matching lifting the finger/releasing the mouse button,
is important when there's a large delay between it and the previous events,
as in when performing a movement, stopping, then releasing fingers as
opposed to doing a swipe.
If this event is skipped, doing this will result in kinetic deceleration
matching the previous finger movement, while the expected behavior would
be no deceleration.
See also 5dc6194b98 for a similar fix in
GtkEventControllerScroll.
GtkAtSpiRoot is not a context, which means it needs to emit
ChildrenChanged events by itself whenever a toplevel is added to, or
removed from, the list of toplevels.
A bit hacky: we skip parsing values that have a reference or
reference-list type, but we do not error out. Instead, we return a NULL
value, which we catch in the GtkBuildable interface implementation to
get the actual object, and construct a reference list value.
There's still some ickyness around the value type that can only be
solved by having an attribute and role taxonomy.
Accessible attributes are not GObject properties. This means that we
need a custom parser for setting attributes in our UI description files.
The new section is defined as a sub-tree with the `<accessibility>`
element at its root, and elements for each type of accessible
attributes, i.e. properties, relations, and states:
```xml
<object class="..." id="...">
<accessibility>
<property name="label">The accessible label</property>
<state name="pressed">false</state>
<relation name="labelled-by">label1</relation>
</accessibility>
</object>
```
The name of the attribute is the enumeration value; the value is defined
by the WAI-ARIA specification.
The nameless, faceless gizmos inside a range do not
contribute to the accessible experience at all, lets
not add them to the tree. All the accessible functionality
is on the main widget (either a scale or a scrollbar).
Show the object path of the object on the a11y bus,
this is can be useful information. While we are here,
make sure that the Inspector does not throw criticals
when used with GTK_NO_A11Y=1.
There were several places where we were confusing
GList and GSList and list->data and list->next, causing
a crash in the accessible name computation for buttons
with mnemonic labels.
Anybody who keeps their own CSS nodes around or wants to order CSS nodes
different from widgets will from now on have to do it manually all the
time.
This is outdated behavior, nobody should be doing either of those two
things.
Also, the correct case is much more common, and not doing it
automatically was causing bugs.
Fixes#3280
The stack page objects were not properly integrated
in the accessible tree - they were appearing as parent
of the pages when navigating up, but not as children
of the stack when navigating down.
Instead of falling back to the role nick for both,
fall back to the class name for the name, and to
the empty string for the description. This makes
labels show up in Accerciser the same way they
did in GTK 3, and seems more useful to me than
the alternative.
The ARIA spec determines the name and description of accessible elements
in a more complex way that simply mapping to a single property; instead,
it will chain up multiple definitions (if it finds them). For instance,
let's assume we have a button that saves a file selected from a file
selection widget; the widgets have the following attributes:
- the file selection widget has a "label" attribute set to the
selected file, e.g. "Final paper.pdf"
- the "download" button has a "label" attribute set to the
"Download" string
- the "download" button has a "labelled-by" attribute set to
reference the file selection widget
The ARIA spec says that the accessible name of the "Download" button
should be computed as "Download Final paper.pdf".
The algorithm defined in section 4.3 of the WAI-ARIA specification
applies to both accessible names (using the "label" and "labelled-by"
attributes), and to accessible descriptions (using the "description" and
"described-by" attributes).
Our Text implementation requires that we have
a GtkEditable with a delegate that is a GtkText
widget.
This change make the Text implementation work for
the custom widget in the tagged entry demo.
Implement the non-questionable parts of the Component interface
for accessibles which are widgets.
This does not include:
- global coordinates
- setters
- scrolling
- alpha, layers, zorder, and the like
Make right-aligned content work in resized columns.
There is currently no way to make a title right-aligned,
but we can still make it work correctly. This is a follow
up to 7eb0ae39c5.
Fixes: #3276
When resizing columns, we clip a shrunk column
on the right, so the separator disappears in that
case unless we put it on the left side of the other
column.
Ensure that the column resize cursor stays in place
for the duration of the resize drag. This is a bit
annoying, since the implicit grab can end up on the
header of a different column from the one we are
resizing, so just set the cursor on all column headers.
Make it so that for overlapping resize rectangles (with
very narrow columns), we prefer the narrow column, so you
can regrow a column after shrinking it all the way.
Related: #3274
Ensure that we place the resize rectangle at the visible
right edge of the column, not where the allocation ends
(we clip the header drawing, after all).
Related: #3274
We only want to show relevant, local actions for
widgets, but _gtk_widget_get_action_muxer() will
return the muxer of a parent widget (all the way
up to the toplevel), if the widget does not have
any actions of its own. To detect this situation,
compare what _gtk_widget_get_action_muxer() returns
for the parent widget, and act accordingly.
