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
Use window title, or custom title widget if it's set. Remove 'title'
property.
Update demos and tests to set the title on the window instead of
headerbar.
Now that the title buttons are encapsulated in a separate widget, use
it in the header bar.
Hide them when empty, so that they don't add extra spacing.
Update the layout when any of the following properties changes:
* modal
* transient-for
* resizable
* deletable
Stop updating it from GtkWindow, make that function static.
Add the following actions:
* window.close
* window.toggle-maximize
* window.minimize
Ensure they are disabled when not appropriate, such as for modal windows.
Use them in GtkHeaderBar.
The application menu isn't particular relevant anymore, and the support for
showing fallback appmenu as a headerbar icon is one of the things tying
GtkWindow to GtkHeaderBar.
Remove support for "menu" window decoration element completely, update
GtkHeaderBar docs.
This was only living in gtkcontainer.c for historic
reasons. Move it closer to where it belongs, and
rename it from 'idle' to 'layout', since it is
really about the layout phase of the frame clock,
nowadays.
The "iconified" state is mostly an X11-ism; every other platform calls
this state "minimized" because it may not involve turning a window into
an icon at all.
The signal handler that calls notify_child_cb() is disconnected
from a child widget before the child is removed from the header bar.
gtk_header_bar_dispose() chains up before destroying the start and end
boxes, thus avoiding calls to notify_child_cb() after start_box and
end_box have been cleared.
Fixes#2246
This allows custom titles to use the vertical alignment of their choice
without having to set it manually after it has been added to the header
bar, hence allowing them to define their preferred alignment from a UI
template.
This is useful for widgets like the view switcher which requires filling
the header bar's whole height.
