gtk4/org.gtkkn.bindings.gtk/EventControllerScroll

EventControllerScroll

open class EventControllerScroll(pointer: <Error class: unknown class><<Error class: unknown class>>) : 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::scroll signal. Deltas in the discrete case are multiples of 1.

In the case of continuous scroll events, GtkEventControllerScroll encloses all signal@Gtk.EventControllerScroll::scroll emissions between two signal@Gtk.EventControllerScroll::scroll-begin and signal@Gtk.EventControllerScroll::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::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::decelerate signal, emitted at the end of scrolling with two X/Y velocity arguments that are consistent with the motion that was received.

Constructors

EventControllerScroll

constructor(flags: EventControllerScrollFlags)

Creates a new event controller that will handle scroll events.

constructor(pointer: <Error class: unknown class><<Error class: unknown class>>)

Types

Companion

object Companion

Properties

flags

open var flags: EventControllerScrollFlags

The flags affecting event controller behavior.

gtkEventControllerPointer

val gtkEventControllerPointer: <Error class: unknown class><<Error class: unknown class>>

gtkEventControllerScrollPointer

val gtkEventControllerScrollPointer: <Error class: unknown class><<Error class: unknown class>>

name

open var name: String?

The name for this controller, typically used for debugging purposes.

propagationLimit

open var propagationLimit: PropagationLimit

The limit for which events this controller will handle.

propagationPhase

open var propagationPhase: PropagationPhase

The propagation phase at which this controller will handle events.

widget

open val widget: Widget?

The widget receiving the GdkEvents that the controller will handle.

Functions

connectDecelerate

fun connectDecelerate(connectFlags: <Error class: unknown class> = ConnectFlags(0u), handler: (velX: Double, velY: Double) -> Unit): <Error class: unknown class>

Emitted after scroll is finished if the %GTK_EVENT_CONTROLLER_SCROLL_KINETIC flag is set.

connectScroll

fun connectScroll(connectFlags: <Error class: unknown class> = ConnectFlags(0u), handler: (dx: Double, dy: Double) -> Boolean): <Error class: unknown class>

Signals that the widget should scroll by the amount specified by @dx and @dy.

connectScrollBegin