Package org.gnome.gtk

Class EventControllerScroll

java.lang.Object

org.javagi.base.ProxyInstance

org.gnome.gobject.TypeInstance

org.gnome.gobject.GObject

org.gnome.gtk.EventController

org.gnome.gtk.EventControllerScroll

All Implemented Interfaces:

Proxy

@Generated("io.github.jwharm.JavaGI")
public class EventControllerScroll
extends EventController

Handles scroll events.

It is capable of handling both discrete and continuous scroll events from mice or touchpads, abstracting them both with the Gtk.EventControllerScroll::scroll signal. Deltas in the discrete case are multiples of 1.

In the case of continuous scroll events, GtkEventControllerScroll encloses all Gtk.EventControllerScroll::scroll emissions between two Gtk.EventControllerScroll::scroll-begin and 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 setFlags(java.util.Set<org.gnome.gtk.EventControllerScrollFlags>) (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 EventControllerScrollFlags.VERTICAL, EventControllerScrollFlags.HORIZONTAL and EventControllerScrollFlags.BOTH_AXES. If any axis is disabled, the respective 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 EventControllerScrollFlags.DISCRETE. This can be used to implement discrete actions triggered through scroll events (e.g. switching across combobox options).

The EventControllerScrollFlags.KINETIC flag toggles the emission of the 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.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	EventControllerScroll.Builder<B extends EventControllerScroll.Builder<B>>	Inner class implementing a builder pattern to construct a GObject with properties.
static interface	EventControllerScroll.DecelerateCallback	Functional interface declaration of the DecelerateCallback callback.
static class	EventControllerScroll.EventControllerScrollClass
static interface	EventControllerScroll.ScrollBeginCallback	Functional interface declaration of the ScrollBeginCallback callback.
static interface	EventControllerScroll.ScrollCallback	Functional interface declaration of the ScrollCallback callback.
static interface	EventControllerScroll.ScrollEndCallback	Functional interface declaration of the ScrollEndCallback callback.

Nested classes/interfaces inherited from class org.gnome.gtk.EventController

EventController.EventController$Impl, EventController.EventControllerClass

Nested classes/interfaces inherited from class org.gnome.gobject.GObject

GObject.NotifyCallback, GObject.ObjectClass

Constructor Summary

Constructors

Constructor	Description
EventControllerScroll()	Creates a new EventControllerScroll.
EventControllerScroll(MemorySegment address)	Create a EventControllerScroll proxy instance for the provided memory address.
EventControllerScroll(Set<EventControllerScrollFlags> flags)	Creates a new event controller that will handle scroll events.
EventControllerScroll(EventControllerScrollFlags... flags)	Creates a new event controller that will handle scroll events.

Method Summary

Modifier and Type	Method	Description
protected EventControllerScroll	asParent()	Returns this instance as if it were its parent type.
static EventControllerScroll.Builder<? extends EventControllerScroll.Builder>	builder()	A EventControllerScroll.Builder object constructs a EventControllerScroll with the specified properties.
void	emitDecelerate(double velX, double velY)	Emits the "decelerate" signal.
boolean	emitScroll(double dx, double dy)	Emits the "scroll" signal.
void	emitScrollBegin()	Emits the "scroll-begin" signal.
void	emitScrollEnd()	Emits the "scroll-end" signal.
Set<EventControllerScrollFlags>	getFlags()	Gets the flags conditioning the scroll controller behavior.
static @Nullable Type	getType()	Get the GType of the EventControllerScroll class
ScrollUnit	getUnit()	Gets the scroll unit of the last Gtk.EventControllerScroll::scroll signal received.
SignalConnection<EventControllerScroll.DecelerateCallback>	onDecelerate(EventControllerScroll.DecelerateCallback handler)	Emitted after scroll is finished if the EventControllerScrollFlags.KINETIC flag is set.
SignalConnection<EventControllerScroll.ScrollCallback>	onScroll(EventControllerScroll.ScrollCallback handler)	Signals that the widget should scroll by the amount specified by dx and dy.
SignalConnection<EventControllerScroll.ScrollBeginCallback>	onScrollBegin(EventControllerScroll.ScrollBeginCallback handler)	Signals that a new scrolling operation has begun.
SignalConnection<EventControllerScroll.ScrollEndCallback>	onScrollEnd(EventControllerScroll.ScrollEndCallback handler)	Signals that a scrolling operation has finished.
void	setFlags(Set<EventControllerScrollFlags> flags)	Sets the flags conditioning scroll controller behavior.
void	setFlags(EventControllerScrollFlags... flags)	Sets the flags conditioning scroll controller behavior.

Methods inherited from class org.gnome.gtk.EventController

getCurrentEvent, getCurrentEventDevice, getCurrentEventState, getCurrentEventTime, getName, getPropagationLimit, getPropagationPhase, getWidget, reset, setName, setPropagationLimit, setPropagationPhase, setStaticName

Methods inherited from class org.gnome.gobject.GObject

addToggleRef, addWeakPointer, bindProperty, bindProperty, bindProperty, bindPropertyFull, bindPropertyFull, bindPropertyWithClosures, bindPropertyWithClosures, compatControl, connect, connect, connect, constructed, disconnect, dispatchPropertiesChanged, dispose, dupData, dupQdata, emit, emitNotify, finalize_, forceFloating, freezeNotify, get, getData, getMemoryLayout, getProperty, getProperty, getProperty, getQdata, getv, interfaceFindProperty, interfaceInstallProperty, interfaceListProperties, isFloating, newInstance, newInstance, newv, notify, notify, notifyByPspec, onNotify, ref, refSink, removeToggleRef, removeWeakPointer, replaceData, replaceQdata, runDispose, set, setData, setDataFull, setProperty, setProperty, setProperty, setQdata, setQdataFull, setv, stealData, stealQdata, takeRef, thawNotify, unref, watchClosure, weakRef, weakUnref, withProperties

Methods inherited from class org.gnome.gobject.TypeInstance

callParent, callParent, cast, getPrivate, readGClass, writeGClass

Methods inherited from class org.javagi.base.ProxyInstance

equals, handle, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Details

EventControllerScroll

public EventControllerScroll(MemorySegment address)

Create a EventControllerScroll proxy instance for the provided memory address.

Parameters:

address - the memory address of the native object

EventControllerScroll

public EventControllerScroll(Set<EventControllerScrollFlags> flags)

Creates a new event controller that will handle scroll events.

Parameters:

flags - flags affecting the controller behavior

EventControllerScroll

public EventControllerScroll(EventControllerScrollFlags... flags)

Creates a new event controller that will handle scroll events.

Parameters:

flags - flags affecting the controller behavior

EventControllerScroll

public EventControllerScroll()

Creates a new EventControllerScroll.

Method Details

getType

public static @Nullable Type getType()

Get the GType of the EventControllerScroll class

Returns:

the GType

asParent

protected EventControllerScroll asParent()

Returns this instance as if it were its parent type. This is mostly synonymous to the Java super keyword, but will set the native typeclass function pointers to the parent type. When overriding a native virtual method in Java, "chaining up" with super.methodName() doesn't work, because it invokes the overridden function pointer again. To chain up, call asParent().methodName(). This will call the native function pointer of this virtual method in the typeclass of the parent type.

Overrides:

asParent in class EventController

getFlags

public Set<EventControllerScrollFlags> getFlags()

Gets the flags conditioning the scroll controller behavior.

Returns:

the controller flags.

getUnit

public ScrollUnit getUnit()

Gets the scroll unit of the last Gtk.EventControllerScroll::scroll signal received.

Always returns ScrollUnit.WHEEL if the EventControllerScrollFlags.DISCRETE flag is set.

Returns:

the scroll unit.

Since:

4.8

setFlags

public void setFlags(Set<EventControllerScrollFlags> flags)

Sets the flags conditioning scroll controller behavior.

Parameters:

flags - flags affecting the controller behavior

setFlags

public void setFlags(EventControllerScrollFlags... flags)

Sets the flags conditioning scroll controller behavior.

Parameters:

flags - flags affecting the controller behavior

onDecelerate

public SignalConnection<EventControllerScroll.DecelerateCallback> onDecelerate(EventControllerScroll.DecelerateCallback handler)

Emitted after scroll is finished if the EventControllerScrollFlags.KINETIC flag is set.

velX and velY express the initial velocity that was imprinted by the scroll events. velX and velY are expressed in pixels/ms.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• EventControllerScroll.DecelerateCallback.run(double, double)

emitDecelerate

public void emitDecelerate(double velX,
 double velY)

Emits the "decelerate" signal. See onDecelerate(org.gnome.gtk.EventControllerScroll.DecelerateCallback).

onScroll

public SignalConnection<EventControllerScroll.ScrollCallback> onScroll(EventControllerScroll.ScrollCallback handler)

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

For the representation unit of the deltas, see getUnit().

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• EventControllerScroll.ScrollCallback.run(double, double)

emitScroll

public boolean emitScroll(double dx,
 double dy)

Emits the "scroll" signal. See onScroll(org.gnome.gtk.EventControllerScroll.ScrollCallback).

onScrollBegin

public SignalConnection<EventControllerScroll.ScrollBeginCallback> onScrollBegin(EventControllerScroll.ScrollBeginCallback handler)

Signals that a new scrolling operation has begun.

It will only be emitted on devices capable of it.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• EventControllerScroll.ScrollBeginCallback.run()

emitScrollBegin

public void emitScrollBegin()

Emits the "scroll-begin" signal. See onScrollBegin(org.gnome.gtk.EventControllerScroll.ScrollBeginCallback).

onScrollEnd

public SignalConnection<EventControllerScroll.ScrollEndCallback> onScrollEnd(EventControllerScroll.ScrollEndCallback handler)

Signals that a scrolling operation has finished.

It will only be emitted on devices capable of it.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• EventControllerScroll.ScrollEndCallback.run()

emitScrollEnd

public void emitScrollEnd()

Emits the "scroll-end" signal. See onScrollEnd(org.gnome.gtk.EventControllerScroll.ScrollEndCallback).

builder

public static EventControllerScroll.Builder<? extends EventControllerScroll.Builder> builder()

A EventControllerScroll.Builder object constructs a EventControllerScroll with the specified properties. Use the various set...() methods to set properties, and finish construction with EventControllerScroll.Builder.build().

Returns:

the builder object