The utility of those signals is somewhat dubious now that there is
gtk_gesture_group(), so make that the only way to coordinate gestures.
The cooperation model offered by gtk_gesture_group() is flexible
enough,
Listen for notify::sequence-state-changed on the controller, so the
only way to manipulate a sequence state are gtk_gesture_set_sequence_state()
and gtk_gesture_set_state().
Also, make use of gesture groups, so the sequence state is set at once
on all gestures pertaining to a single group. Within a widget, if a sequence
is claimed on one group, it is made to be denied on every other group.
This API eliminates the need for overriding
GtkWidget::sequence-state-changed virtually everywhere. Grouped
gestures share common states for a same GdkEventSequence, so the
state of sequences stay in sync across those.
A multipress gesture is used to control all this, replacing
single/double click custom code, and triggering window dragging
when the multipress is stopped, yet active (ie. the sequence remains
pressed).
This gesture is used by gtk_drag_source_set() to determine
whether dragging moved past the threshold. The gesture events
are handled via the usual ::event callbacks, so we don't mess
up with callers expecting that to happen in a signal handler.
If the sequence gets claimed somewhere else in the event widget
stack, the DnD gesture will be cancelled.
With gtk_gesture_get_point() returning events in
gtk_event_controller_get_widget() coordinates, we no longer need
to compensate for the overshoot here.
GtkEventController may be certainly useful to keep event
handling self-contained in other places than gestures, but
the current widget API is highly related to gestures, so
just using GtkGesture as the argument there will be quite
more convenient. The other places where GtkEventController
make sense as a base object will better provide their own
hooks.
Gestures attached with this phase will expect callers to have it
receive events through gtk_event_controller_handle_event(), but
the gesture will still be notified of sequence state changes,
grabs, etc...
Translate events meant for other widgets/windows, so gtk_gesture_get_point()
always returns coordinates based on the gtk_event_controller_get_widget()
allocation.
If a gesture has denied sequences (so those are presumably handled above/below
the widget), it shouldn't attempt to handle extra touches, even if those end
up matching the expected number of touches.
Gestures should always receive one of such events in order to be activated,
and the propagation mechanism will ensure they do so if the original event
was caught up the widget hierarchy by another gesture that is now declining
the sequence.
If the captured touch begin or button press event have been consumed
for the given sequence, propagate it upwards if the sequence goes from
claimed to denied, so the widgets on the way to the event widget receive
a coherent event stream now that they're going to receive events.
The policy of sequence states has been made tighter on GtkGesture,
so gestures can never return to a "none" state, nor get out of a
"denied" state, a "claimed" sequence can go "denied" though.
The helper API at the widget level will first emit
GtkWidget::sequence-state-changed on the called widget, and then
notify through the same signal to every other widget in the captured
event chain. So the effect of that signal is twofold, on one hand
it lets the original widget set the state on its attached controllers,
and on the other hand it lets the other widgets freely adapt to the
sequence state changing elsewhere in the event widget chain.
By default, that signal updates every controller on the first usecase,
and propagates the default gesture policy to every other widget in the
chain on the second. This means that, by default:
1) Sequences start out on the "none" state, and get propagated through
all the event widget chain.
2) If a widget in the chain denies the sequence, all other widgets are
unaffected.
3) If a widget in the chain claims the sequence, then:
3.1) Every widget below the claiming widget (ie. towards the event widget)
will get the sequence cancelled.
3.2) Every widget above the claiming widget that had the sequence as "none"
will remain as such, if it was claimed it will go denied, but that should
rarely happen.
This behavior can be tweaked through the GtkWidget::sequence-state-changed and
GtkGesture::event-handled vmethods, although this should be very rarely done.
The kinetic scrolling feature is now implemented using a
GtkGestureDrag and a GtkGestureSwipe, plus a GtkGestureLongPress
in order to denying the sequence, so it is possibly handled
underneath.
A controller can be optionally hooked on the capture or the bubble
phase, so the controller will automatically receive and handle events
as they arrive without further interaction.
Now, all captured events run from the toplevel to the deepmost widget,
regardless of GTK+ grabs. This makes captured events more useful to
event controllers if used together in the hierarchy with widgets doing
old fashioned event handling and GTK+ grabs.
This gesture handles any number of clicks, ensuring multiple presses
stay within thresholds and timeouts. When anything of that happens,
the gesture is reset and press count starts from 1 again.
Optionally, the gesture can be given a rectangle, used in in presses > 1
to ensure the consecutive presses happen on user imposed areas.
This gesture implementation recognices swipes on any direction.
The "swipe" signal has the X/Y velocity vector components, so
those can be used for direction guessing and velocity thresholds.
The change to take out unneeded NULL checks requires some care
at startup: we check both adjustments when any of them changes;
we need to do those checks in the same order in which we create
the scrollbars, otherwise we'll try to get the adjustment of
the vscrollbar when we just set the up the hscrollbars' adjustment.
When the color editor is visible, there is no way for the
application to know about the changes that are happening.
Fix this by emitting property notification for the "rgba"
property.
http://bugzilla.gnome.org/show_bug.cgi?id=708037
This avoids a bunch of policy problems with deciding how to lay
out the window menu under different WMs.
For now, we use the special event _GTK_SHOW_WINDOW_MENU, but we
hope to have this standardized in wm-spec quite soon, as KDE wants
it as well.
We see an active link when creating the menu, but by the time
the menuitem is activated, we've received a leave notify that
makes the label clear its active link. Instead, give the
menuitems a direct reference to the link that is active when
the menu is created.
Problem pointed out by Tim Baedert
We know the objects in a size group are always widgets, so we
can avoid hard-to-track down problems with weak references by
just cleaning up when the object gets destroyed. There is still
a chance that we show a widget as part of the group after it
has been removed, but size groups simply have no signals that
would let us avoid that.
Add a tab that shows size groups of a widget. The properties
of the size group are available here, as well as the widgets
that are part of the size group. We highlight the widgets in
the application when their row in the inspector is hovered.
In contrast to the flashing, where we blink the widget a
few times, this is explicitly turned on and off.
It will be used for indicating widgets that are part of
a size group, in the next commit.
