It won't stand true anymore that the GdkEventType argument is the
first field of the GdkEvent* structs. All callers have been updated
to use event->any.type instead.
Instead of just passing the GdkContentFormats, we are now passing the
GdkContentProvider to gdk_drag_begin().
This means that GDK itself can now query the data from the provider
directly instead of having to send selection events.
Use this to provide the private API gdk_drag_context_write() that allows
backends to pass an output stream that this data will be written to.
Implement this as the mechanism for providing drag data on Wayland.
And to make this all work, implement a content provider named
GtkDragContent that is implemented by reverting to the old DND
drag-data-get machinery inside GTK, so for widgets everything works just
like before.
Instead, pass the actions as part of gdk_drag_begin() and insist DND is
always managed.
A new side effect is that gdk_drag_begin() can now return %NULL.
This is the replacement for selection usage.
Backend implementations for X11 (missing support for backwards compat
formats like COMPOUND_TEXT) and Wayland are included.
GTK code should be adapted to use gdk_drop_read_*() functions instead
of gtk_drag_get_data().
Make sure the API reflects the idea that GdkContentFormats is a set
containing mime types. In particular, treat the object itself as a
plural - it's named content format`S' after all - and therefor use
the correct verb form.
Also make GdkContentFormats keep an array instead of a list, now that
it's immutable.
Drop the screen argument from gdk_dnd_find_window_for_screen
and rename the function to gdk_dnd_find_window. The screen
argument does not add anything here since the drag context
is already tied to the display. Update all backends, and
update all callers.
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.
Under X, we were not setting the right drag cursor initially,
because at current_action == action == 0, initially. Fix this
by explicitly using the right cursor when grabbing.
Otherwise we wait for the next gdk_drag_motion() call, which will
happen on the next motion event, making the drag window briefly visible
on the 0,0 root coordinates.
https://bugzilla.gnome.org/show_bug.cgi?id=778203
Switch code to use gdk_display_is_composited() instead.
The new code also doesn't use a vfunc to query the property but rather
requires the backend to call set_composited()/set_rgba() to change the
value.
These complicate a lot of GdkWindow internals to implement features
that not a lot of apps use, and will be better achieved using gsk.
So, we just drop it all.
And with it, gtk_widget_get_visual() and gtk_widget_set_visual() are
gone.
We now always use the RGBA visual (if available) and otherwise fall back
to the system visual.
... and gdk_screen_get_width_mm() and gdk_screen_get_height_mm() and
the shortcut counterparts that call these functions on the default
screen.
Modern display servers don't provide an ability to query the size of a
screen or display so we shouldn't allow that either.
The GdkDragContext should only listen to GDK_GRAB_BROKEN events sent to
its own pointer device. It turns out that the passive key grabs mistake
GDK into sending a GdkEventGrabBroken on the master keyboard, which the
DnD machinery mistakes as a signal to cancel the operation.
https://bugzilla.gnome.org/show_bug.cgi?id=766442
The active keyboard grab can be spared then. This way the passive
key grabs allow other key combinations (eg. alt-tab) that are not
mandatory to grab here.
Always associate a drag context with a GdkDisplay and use that when
getting a cursor for a given action.
If we don't do this, dragging on a window that doesn't use the default
display will make us use cursors from the wrong display.
https://bugzilla.gnome.org/show_bug.cgi?id=765565
We were just relying on the drag context finalize() to destroy
the window. But with garbage-collected bindings, that might
not happen as soon as we like, so explicitly hide the window
when the drag ends successfully.
https://bugzilla.gnome.org/show_bug.cgi?id=763659
