EventControllerScroll

gtk.EventControllerScroll 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 scroll signal (deltas in the discrete case are multiples of 1).

In the case of continuous scroll events, gtk.EventControllerScroll encloses all scroll events between two scroll-begin and 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 Event.controllerScrollSetFlags (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 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 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

this
this(GtkEventControllerScroll* gtkEventControllerScroll, bool ownedRef)

Sets our main struct and passes it to the parent class.

this
this(Widget widget, GtkEventControllerScrollFlags flags)

Creates a new event controller that will handle scroll events for the given widget.

Members

Functions

addOnDecelerate
gulong addOnDecelerate(void delegate(double, double, EventControllerScroll) dlg, ConnectFlags connectFlags)

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.

addOnScroll
gulong addOnScroll(void delegate(double, double, EventControllerScroll) dlg, ConnectFlags connectFlags)

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

addOnScrollBegin
gulong addOnScrollBegin(void delegate(EventControllerScroll) dlg, ConnectFlags connectFlags)

Signals that a new scrolling operation has begun. It will only be emitted on devices capable of it.

addOnScrollEnd
gulong addOnScrollEnd(void delegate(EventControllerScroll) dlg, ConnectFlags connectFlags)

Signals that a new scrolling operation has finished. It will only be emitted on devices capable of it.

getEventControllerScrollStruct
GtkEventControllerScroll* getEventControllerScrollStruct(bool transferOwnership)

Get the main Gtk struct

getFlags
GtkEventControllerScrollFlags getFlags()

Gets the flags conditioning the scroll controller behavior.

getStruct
void* getStruct()

the main Gtk struct as a void*

setFlags
void setFlags(GtkEventControllerScrollFlags flags)

Sets the flags conditioning scroll controller behavior.

Static functions

getType
GType getType()

Variables

gtkEventControllerScroll
GtkEventControllerScroll* gtkEventControllerScroll;

the main Gtk struct

Inherited Members

From EventController

gtkEventController
GtkEventController* gtkEventController;

the main Gtk struct

getEventControllerStruct
GtkEventController* getEventControllerStruct(bool transferOwnership)

Get the main Gtk struct

getStruct
void* getStruct()

the main Gtk struct as a void*

getType
GType getType()
getPropagationPhase
GtkPropagationPhase getPropagationPhase()

Gets the propagation phase at which controller handles events.

getWidget
Widget getWidget()

Returns the gtk.Widget this controller relates to.

handleEvent
bool handleEvent(Event event)

Feeds an events into controller, so it can be interpreted and the controller actions triggered.

reset
void reset()

Resets the controller to a clean state. Every interaction the controller did through handle-event will be dropped at this point.

setPropagationPhase
void setPropagationPhase(GtkPropagationPhase phase)

Sets the propagation phase at which a controller handles events.