Class
GtkEventControllerScroll
Description [src]
final class Gtk.EventControllerScroll : Gtk.EventController
{
/* No available fields */
}GtkEventControllerScroll is an event controller meant to handle
scroll events from mice and touchpads. It is capable of handling
both discrete and continuous scroll events, abstracting them both
on the GtkEventControllerScroll::scroll signal (deltas in the
discrete case are multiples of 1).
In the case of continuous scroll events, GtkEventControllerScroll
encloses all GtkEventControllerScroll::scroll events between two
GtkEventControllerScroll::scroll-begin and GtkEventControllerScroll::scroll-end
signals.
The behavior of the event controller can be modified by the
flags given at creation time, or modified at a later point through
gtk_event_controller_scroll_set_flags() (e.g. because the scrolling
conditions of the widget changed).
The controller can be set up to emit motion for either/both vertical and horizontal scroll events through #GTK_EVENT_CONTROLLER_SCROLL_VERTICAL,
GTK_EVENT_CONTROLLER_SCROLL_HORIZONTAL and #GTK_EVENT_CONTROLLER_SCROLL_BOTH.
If any axis is disabled, the respective GtkEventControllerScroll::scroll
delta will be 0. Vertical scroll events will be translated to horizontal
motion for the devices incapable of horizontal scrolling.
The event controller can also be forced to emit discrete events on all devices through #GTK_EVENT_CONTROLLER_SCROLL_DISCRETE. This can be used to implement discrete actions triggered through scroll events (e.g. switching across combobox options).
The #GTK_EVENT_CONTROLLER_SCROLL_KINETIC flag toggles the emission of the
GtkEventControllerScroll::decelerate signal, emitted at the end of scrolling
with two X/Y velocity arguments that are consistent with the motion that
was received.
This object was added in 3.24.
Constructors
gtk_event_controller_scroll_new
Creates a new event controller that will handle scroll events
for the given widget.
since: 3.24
Instance methods
gtk_event_controller_scroll_get_flags
Gets the flags conditioning the scroll controller behavior.
since: 3.24
gtk_event_controller_scroll_set_flags
Sets the flags conditioning scroll controller behavior.
since: 3.24
Methods inherited from GtkEventController (5)
gtk_event_controller_get_propagation_phase
Gets the propagation phase at which controller handles events.
since: 3.14
gtk_event_controller_get_widget
Returns the GtkWidget this controller relates to.
since: 3.14
gtk_event_controller_handle_event
Feeds an events into controller, so it can be interpreted
and the controller actions triggered.
since: 3.14
gtk_event_controller_reset
Resets the controller to a clean state. Every interaction
the controller did through GtkEventController::handle-event
will be dropped at this point.
since: 3.14
gtk_event_controller_set_propagation_phase
Sets the propagation phase at which a controller handles events.
since: 3.14
Properties
Properties inherited from GtkEventController (2)
Gtk.EventController:propagation-phase
The propagation phase at which this controller will handle events.
since: 3.14
Gtk.EventController:widget
The widget receiving the GdkEvents that the controller will handle.
since: 3.14
Signals
Gtk.EventControllerScroll::decelerate
Emitted after scroll is finished if the #GTK_EVENT_CONTROLLER_SCROLL_KINETIC
flag is set. vel_x and vel_y express the initial velocity that was
imprinted by the scroll events. vel_x and vel_y are expressed in pixels/ms.
Gtk.EventControllerScroll::scroll
Signals that the widget should scroll by the
amount specified by dx and dy.
Gtk.EventControllerScroll::scroll-begin
Signals that a new scrolling operation has begun. It will only be emitted on devices capable of it.
Gtk.EventControllerScroll::scroll-end
Signals that a new scrolling operation has finished. It will only be emitted on devices capable of it.
Signals inherited from GObject (1)
GObject::notify
The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.