EventControllerScroll
Object Hierarchy:
Description:
public sealed class EventControllerScroll : EventController
`GtkEventControllerScroll` is an event controller that handles scroll events.
It is capable of handling both discrete and continuous scroll events from mice or touchpads, abstracting them both with the [
signal@Gtk.EventControllerScroll:GtkEventControllerScroll:scroll] signal. Deltas in the discrete case are multiples of 1.
In the case of continuous scroll events, `GtkEventControllerScroll` encloses all [signal@Gtk.EventControllerScroll:
GtkEventControllerScroll:scroll] emissions between two [signal@Gtk.EventControllerScroll:GtkEventControllerScroll:scroll-begin
] and [signal@Gtk.EventControllerScroll: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 [ method@Gtk.EventControllerScroll.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_axes. If any axis is disabled, the respective [
signal@Gtk.EventControllerScroll: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 [signal@Gtk.EventControllerScroll:
GtkEventControllerScroll:decelerate] signal, emitted at the end of scrolling with two X/Y velocity arguments that are consistent
with the motion that was received.