This is a huge reorganization of GtkDropTarget. I did not know how to
split this up, so it's unfortunately all one commit.
Highlights:
- Split GtkDropTarget into GtkDropTarget and GtkDropTargetAsync
GtkDropTarget is the simple one that only works with GTypes and offers
a synchronous interface.
GtkDropTargetAsync retains the full old functionality and allows
handling mime types.
- Drop events are handled differently
Instead of picking a single drop target and sending all DND events to
it, every event is sent to every drop target. The first one to handle
the event gets to call gdk_drop_status(), further handlers do not
interact with the GdkDrop.
Of course, for the ultimate GDK_DROP_STARTING event, only the first
one to accept the drop gets to handle it.
This allows stacking DND event controllers that aren't necessarily
interested in handling the event or that might decide later to drop
it.
- Port all widgets to either of those
Both have a somewhat changed API due to the new event handling.
For the ones who should use the sync version, lots of cleanup was
involved to operate on a sync API.
Emit crossing events - with a new GTK_CROSSING_DROP type - like we do
for motion events. There is no more special casing for them.
Note that the gesture has not been updated yet, so some obscure behavior
may occur.
Restructure the getters for event fields to
be more targeted at particular event types.
Update all callers, and replace all direct
event struct access with getters.
As a side-effect, this drops some unused getters.
If there is a passive grab and the pointer leaves the window we would
receive a GDK_CROSSING_NORMAL event when the pointer moves outside
the window, and a GDK_CROSSING_UNGRAB event when we do release the
button and the implicit grab.
We currently would react to the first, but want to react to the
second. In the time between both events, the client would still receive
pointer motion that will reach the implicitly grabbed widget.
Closes: https://gitlab.gnome.org/GNOME/gtk/issues/13
Fixes gtk_main_sync() to only remove a source if it has not
already executed (and been removed). The previous code was
using gtk_main_quit() directly which would be non-determinstic
based on the previous value in the return register.
If there is no display, we will hit the slow path here which
can introduce long latencies in unit tests. This checks for
a NULL list of displays and simply short-circuits.
This works just fine, now that drop targets are
event controllers. There is only a very vestigial
gtk_drag_dest_handle_event() left that deals with
corner cases.
G_ENABLE_DEBUG is tied to the meson builttype property, so building with "plain"
results in G_ENABLE_DEBUG not being defined and the GTK_DEBUG env var just gets ignored
for that build.
Since it can be confusing that GTK_DEBUG has no effect print a warning message instead.
See #2020. This is a port of !1109 to master
The new rule for focus events from the windowing
system is: We only want them for toplevels. If you
put focus on popups, we don't want to know about
it, and you still need to deliver key events to
the toplevel.
