EventControllerScrollProtocol

public protocol EventControllerScrollProtocol : EventControllerProtocol

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 [signalGtk.EventControllerScroll::scroll] signal. Deltas in the discrete case are multiples of 1.

In the case of continuous scroll events, GtkEventControllerScroll encloses all [signalGtk.EventControllerScroll::scroll] emissions between two [signalGtk.EventControllerScroll::scroll-begin] and [signalGtk.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 methodGtk.EventControllerScroll.set_flags.

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 [signalGtk.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 [signalGtk.EventControllerScroll::decelerate] signal, emitted at the end of scrolling with two X/Y velocity arguments that are consistent with the motion that was received.

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.

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  • ptr

    Untyped pointer to the underlying GtkEventControllerScroll instance.

    Declaration

    Swift

    var ptr: UnsafeMutableRawPointer! { get }
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  • event_controller_scroll_ptr Default implementation

    Typed 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 }
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  • Required Initialiser for types conforming to EventControllerScrollProtocol

    Declaration

    Swift

    init(raw: UnsafeMutableRawPointer)
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EventControllerScroll Class

  • 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 transformation
    transform_to

    ValueTransformer to use for backwards transformation

    Return Value

    binding reference or nil in case of an error

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  • 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

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  • set(property:value:) Extension method

    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

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EventControllerScroll signals

  • Connect a Swift signal handler to the given, typed EventControllerScrollSignalName signal

    Declaration

    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 by userData
    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)

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  • Connect a C signal handler to the given, typed EventControllerScrollSignalName signal

    Declaration

    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 by userData
    signalHandler

    The C function to be called on the given signal

    Return Value

    The signal handler ID (always greater than 0 for successful connections)

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  • onDecelerate(flags:handler:) Extension method

    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.

    Note

    This represents the underlying decelerate signal

    Declaration

    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
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  • decelerateSignal Extension method

    Typed decelerate signal for using the connect(signal:) methods

    Declaration

    Swift

    static var decelerateSignal: EventControllerScrollSignalName { get }
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  • onScroll(flags:handler:) Extension method

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

    Note

    This represents the underlying scroll signal

    Declaration

    Swift

    @discardableResult
@inlinable
func onScroll(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: EventControllerScrollRef, _ dx: Double, _ dy: Double) -> Bool) -> Int

    Parameters

    flags

    Flags
    unownedSelf

    Reference to instance of self
    dx

    X delta
    dy

    Y delta
    handler

    true if the scroll event was handled, false otherwise. Run the given callback whenever the scroll signal is emitted
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  • scrollSignal Extension method

    Typed scroll signal for using the connect(signal:) methods

    Declaration

    Swift

    static var scrollSignal: EventControllerScrollSignalName { get }
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  • Signals that a new scrolling operation has begun.

    It will only be emitted on devices capable of it.

    Note

    This represents the underlying scroll-begin signal

    Declaration

    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
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  • scrollBeginSignal Extension method

    Typed scroll-begin signal for using the connect(signal:) methods

    Declaration

    Swift

    static var scrollBeginSignal: EventControllerScrollSignalName { get }
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  • onScrollEnd(flags:handler:) Extension method

    Signals that a scrolling operation has finished.

    It will only be emitted on devices capable of it.

    Note

    This represents the underlying scroll-end signal

    Declaration

    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
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  • scrollEndSignal Extension method

    Typed scroll-end signal for using the connect(signal:) methods

    Declaration

    Swift

    static var scrollEndSignal: EventControllerScrollSignalName { get }
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  • 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 to g_object_set_property() results in notify being emitted, even if the new value is the same as the old. If they did pass G_PARAM_EXPLICIT_NOTIFY, then this signal is emitted only when they explicitly call g_object_notify() or g_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 underlying notify::flags signal

    Declaration

    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
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  • notifyFlagsSignal Extension method

    Typed notify::flags signal for using the connect(signal:) methods

    Declaration

    Swift

    static var notifyFlagsSignal: EventControllerScrollSignalName { get }
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EventControllerScroll Class: EventControllerScrollProtocol extension (methods and fields)