EventControllerScrollProtocol
public protocol EventControllerScrollProtocol : EventControllerProtocol
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.
The EventControllerScrollProtocol
protocol exposes the methods and properties of an underlying GtkEventControllerScroll
instance.
The default implementation of these can be found in the protocol extension below.
For a concrete class that implements these methods and properties, see EventControllerScroll
.
Alternatively, use EventControllerScrollRef
as a lighweight, unowned
reference if you already have an instance you just want to use.
-
Untyped pointer to the underlying
GtkEventControllerScroll
instance.Declaration
Swift
var ptr: UnsafeMutableRawPointer! { get }
-
event_controller_scroll_ptr
Default implementationTyped pointer to the underlying
GtkEventControllerScroll
instance.Default Implementation
Return the stored, untyped pointer as a typed pointer to the
GtkEventControllerScroll
instance.Declaration
Swift
var event_controller_scroll_ptr: UnsafeMutablePointer<GtkEventControllerScroll>! { get }
-
Required Initialiser for types conforming to
EventControllerScrollProtocol
Declaration
Swift
init(raw: UnsafeMutableRawPointer)
-
bind(property:
Extension methodto: _: flags: transformFrom: transformTo: ) Bind a
EventControllerScrollPropertyName
source property to a given target object.Declaration
Swift
@discardableResult @inlinable func bind<Q, T>(property source_property: EventControllerScrollPropertyName, to target: T, _ target_property: Q, flags f: BindingFlags = .default, transformFrom transform_from: @escaping GLibObject.ValueTransformer = { $0.transform(destValue: $1) }, transformTo transform_to: @escaping GLibObject.ValueTransformer = { $0.transform(destValue: $1) }) -> BindingRef! where Q : PropertyNameProtocol, T : ObjectProtocol
Parameters
source_property
the source property to bind
target
the target object to bind to
target_property
the target property to bind to
flags
the flags to pass to the
Binding
transform_from
ValueTransformer
to use for forward transformationtransform_to
ValueTransformer
to use for backwards transformationReturn Value
binding reference or
nil
in case of an error -
get(property:
Extension method) Get the value of a EventControllerScroll property
Declaration
Swift
@inlinable func get(property: EventControllerScrollPropertyName) -> GLibObject.Value
Parameters
property
the property to get the value for
Return Value
the value of the named property
-
set(property:
Extension methodvalue: ) Set the value of a EventControllerScroll property. Note that this will only have an effect on properties that are writable and not construct-only!
Declaration
Swift
@inlinable func set(property: EventControllerScrollPropertyName, value v: GLibObject.Value)
Parameters
property
the property to get the value for
Return Value
the value of the named property
-
connect(signal:
Extension methodflags: handler: ) Connect a Swift signal handler to the given, typed
EventControllerScrollSignalName
signalDeclaration
Swift
@discardableResult @inlinable func connect(signal s: EventControllerScrollSignalName, flags f: ConnectFlags = ConnectFlags(0), handler h: @escaping SignalHandler) -> Int
Parameters
signal
The signal to connect
flags
The connection flags to use
data
A pointer to user data to provide to the callback
destroyData
A
GClosureNotify
C function to destroy the data pointed to byuserData
handler
The Swift signal handler (function or callback) to invoke on the given signal
Return Value
The signal handler ID (always greater than 0 for successful connections)
-
connect(signal:
Extension methodflags: data: destroyData: signalHandler: ) Connect a C signal handler to the given, typed
EventControllerScrollSignalName
signalDeclaration
Swift
@discardableResult @inlinable func connect(signal s: EventControllerScrollSignalName, flags f: ConnectFlags = ConnectFlags(0), data userData: gpointer!, destroyData destructor: GClosureNotify? = nil, signalHandler h: @escaping GCallback) -> Int
Parameters
signal
The signal to connect
flags
The connection flags to use
data
A pointer to user data to provide to the callback
destroyData
A
GClosureNotify
C function to destroy the data pointed to byuserData
signalHandler
The C function to be called on the given signal
Return Value
The signal handler ID (always greater than 0 for successful connections)
-
onDecelerate(flags:
Extension methodhandler: ) Emitted after scroll is finished if the
GTK_EVENT_CONTROLLER_SCROLL_KINETIC
flag is set.vel_x
andvel_y
express the initial velocity that was imprinted by the scroll events.vel_x
andvel_y
are expressed in pixels/ms.Note
This represents the underlyingdecelerate
signalDeclaration
Swift
@discardableResult @inlinable func onDecelerate(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: EventControllerScrollRef, _ velX: Double, _ velY: Double) -> Void) -> Int
Parameters
flags
Flags
unownedSelf
Reference to instance of self
velX
X velocity
velY
Y velocity
handler
The signal handler to call Run the given callback whenever the
decelerate
signal is emitted -
decelerateSignal
Extension methodTyped
decelerate
signal for using theconnect(signal:)
methodsDeclaration
Swift
static var decelerateSignal: EventControllerScrollSignalName { get }
-
onScroll(flags:
Extension methodhandler: ) Signals that the widget should scroll by the amount specified by
dx
anddy
.Note
This represents the underlyingscroll
signalDeclaration
Swift
@discardableResult @inlinable func onScroll(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: EventControllerScrollRef, _ dx: Double, _ dy: Double) -> Void) -> Int
Parameters
flags
Flags
unownedSelf
Reference to instance of self
dx
X delta
dy
Y delta
handler
The signal handler to call Run the given callback whenever the
scroll
signal is emitted -
scrollSignal
Extension methodTyped
scroll
signal for using theconnect(signal:)
methodsDeclaration
Swift
static var scrollSignal: EventControllerScrollSignalName { get }
-
onScrollBegin(flags:
Extension methodhandler: ) Signals that a new scrolling operation has begun. It will only be emitted on devices capable of it.
Note
This represents the underlyingscroll-begin
signalDeclaration
Swift
@discardableResult @inlinable func onScrollBegin(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: EventControllerScrollRef) -> Void) -> Int
Parameters
flags
Flags
unownedSelf
Reference to instance of self
handler
The signal handler to call Run the given callback whenever the
scrollBegin
signal is emitted -
scrollBeginSignal
Extension methodTyped
scroll-begin
signal for using theconnect(signal:)
methodsDeclaration
Swift
static var scrollBeginSignal: EventControllerScrollSignalName { get }
-
onScrollEnd(flags:
Extension methodhandler: ) Signals that a new scrolling operation has finished. It will only be emitted on devices capable of it.
Note
This represents the underlyingscroll-end
signalDeclaration
Swift
@discardableResult @inlinable func onScrollEnd(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: EventControllerScrollRef) -> Void) -> Int
Parameters
flags
Flags
unownedSelf
Reference to instance of self
handler
The signal handler to call Run the given callback whenever the
scrollEnd
signal is emitted -
scrollEndSignal
Extension methodTyped
scroll-end
signal for using theconnect(signal:)
methodsDeclaration
Swift
static var scrollEndSignal: EventControllerScrollSignalName { get }
-
onNotifyFlags(flags:
Extension methodhandler: ) 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.Note that getting this signal doesn’t itself guarantee that the value of the property has actually changed. When it is emitted is determined by the derived GObject class. If the implementor did not create the property with
G_PARAM_EXPLICIT_NOTIFY
, then any call tog_object_set_property()
results innotify
being emitted, even if the new value is the same as the old. If they did passG_PARAM_EXPLICIT_NOTIFY
, then this signal is emitted only when they explicitly callg_object_notify()
org_object_notify_by_pspec()
, and common practice is to do that only when the value has actually changed.This signal is typically used to obtain change notification for a single property, by specifying the property name as a detail in the
g_signal_connect()
call, like this:(C Language Example):
g_signal_connect (text_view->buffer, "notify::paste-target-list", G_CALLBACK (gtk_text_view_target_list_notify), text_view)
It is important to note that you must use canonical parameter names as detail strings for the notify signal.
Note
This represents the underlyingnotify::flags
signalDeclaration
Swift
@discardableResult @inlinable func onNotifyFlags(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: EventControllerScrollRef, _ pspec: ParamSpecRef) -> Void) -> Int
Parameters
flags
Flags
unownedSelf
Reference to instance of self
pspec
the
GParamSpec
of the property which changed.handler
The signal handler to call Run the given callback whenever the
notifyFlags
signal is emitted -
notifyFlagsSignal
Extension methodTyped
notify::flags
signal for using theconnect(signal:)
methodsDeclaration
Swift
static var notifyFlagsSignal: EventControllerScrollSignalName { get }
-
getFlags()
Extension methodGets the flags conditioning the scroll controller behavior.
Declaration
Swift
@inlinable func getFlags() -> EventControllerScrollFlags
-
set(flags:
Extension method) Sets the flags conditioning scroll controller behavior.
Declaration
Swift
@inlinable func set(flags: EventControllerScrollFlags)
-
flags
Extension methodThe flags affecting event controller behavior
Declaration
Swift
@inlinable var flags: EventControllerScrollFlags { get nonmutating set }