GI.Gtk.Objects.EventControllerScroll

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, EventControllerScroll encloses all scroll events between two scrollBegin and scrollEnd signals.

The behavior of the event controller can be modified by the flags given at creation time, or modified at a later point through eventControllerScrollSetFlags (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.

Exported types

newtype EventControllerScroll

Memory-managed wrapper type.

Constructors

EventControllerScroll (ManagedPtr EventControllerScroll)

Instances

Eq EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

Methods

(==) :: EventControllerScroll -> EventControllerScroll -> Bool

(/=) :: EventControllerScroll -> EventControllerScroll -> Bool

IsGValue EventControllerScroll

Convert EventControllerScroll to and from GValue with toGValue and fromGValue.

Defined in GI.Gtk.Objects.EventControllerScroll

Methods

toGValue :: EventControllerScroll -> IO GValue

fromGValue :: GValue -> IO EventControllerScroll

GObject EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

Methods

gobjectType :: IO GType

HasParentTypes EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

type ParentTypes EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

type ParentTypes EventControllerScroll = '[EventController, Object]

class (GObject o, IsDescendantOf EventControllerScroll o) => IsEventControllerScroll o

Type class for types which can be safely cast to EventControllerScroll, for instance with toEventControllerScroll.

Instances

(GObject o, IsDescendantOf EventControllerScroll o) => IsEventControllerScroll o

Defined in GI.Gtk.Objects.EventControllerScroll

toEventControllerScroll :: (MonadIO m, IsEventControllerScroll o) => o -> m EventControllerScroll

Cast to EventControllerScroll, for types for which this is known to be safe. For general casts, use castTo.

noEventControllerScroll :: Maybe EventControllerScroll

A convenience alias for Nothing :: Maybe EventControllerScroll.

Methods

Overloaded methods

getFlags

eventControllerScrollGetFlags

Arguments

:: (HasCallStack, MonadIO m, IsEventControllerScroll a)

=> a

scroll: a EventControllerScroll

-> m [EventControllerScrollFlags]

Returns: the controller flags.

Gets the flags conditioning the scroll controller behavior.

new

eventControllerScrollNew

Arguments

:: (HasCallStack, MonadIO m)

=> [EventControllerScrollFlags]

flags: behavior flags

-> m EventControllerScroll

Returns: a new EventControllerScroll

Creates a new event controller that will handle scroll events.

setFlags

eventControllerScrollSetFlags

Arguments

:: (HasCallStack, MonadIO m, IsEventControllerScroll a)

=> a

scroll: a EventControllerScroll

-> [EventControllerScrollFlags]

flags: behavior flags

-> m ()

Sets the flags conditioning scroll controller behavior.

Properties

flags

The flags affecting event controller behavior

constructEventControllerScrollFlags :: IsEventControllerScroll o => [EventControllerScrollFlags] -> IO (GValueConstruct o)

Construct a GValueConstruct with valid value for the “flags” property. This is rarely needed directly, but it is used by new.

getEventControllerScrollFlags :: (MonadIO m, IsEventControllerScroll o) => o -> m [EventControllerScrollFlags]

Get the value of the “flags” property. When overloading is enabled, this is equivalent to

get eventControllerScroll #flags

setEventControllerScrollFlags :: (MonadIO m, IsEventControllerScroll o) => o -> [EventControllerScrollFlags] -> m ()

Set the value of the “flags” property. When overloading is enabled, this is equivalent to

set eventControllerScroll [ #flags := value ]

Signals

decelerate

type C_EventControllerScrollDecelerateCallback = Ptr () -> CDouble -> CDouble -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type EventControllerScrollDecelerateCallback

Arguments

 = Double

velX: X velocity

-> Double

velY: Y velocity

-> IO ()

Emitted after scroll is finished if the GTK_EVENT_CONTROLLER_SCROLL_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.

afterEventControllerScrollDecelerate :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollDecelerateCallback -> m SignalHandlerId

Connect a signal handler for the decelerate signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after eventControllerScroll #decelerate callback

genClosure_EventControllerScrollDecelerate :: MonadIO m => EventControllerScrollDecelerateCallback -> m (GClosure C_EventControllerScrollDecelerateCallback)

Wrap the callback into a GClosure.

mk_EventControllerScrollDecelerateCallback :: C_EventControllerScrollDecelerateCallback -> IO (FunPtr C_EventControllerScrollDecelerateCallback)

Generate a function pointer callable from C code, from a C_EventControllerScrollDecelerateCallback.

noEventControllerScrollDecelerateCallback :: Maybe EventControllerScrollDecelerateCallback

A convenience synonym for Nothing :: Maybe EventControllerScrollDecelerateCallback.

onEventControllerScrollDecelerate :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollDecelerateCallback -> m SignalHandlerId

Connect a signal handler for the decelerate signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on eventControllerScroll #decelerate callback

wrap_EventControllerScrollDecelerateCallback :: EventControllerScrollDecelerateCallback -> C_EventControllerScrollDecelerateCallback

Wrap a EventControllerScrollDecelerateCallback into a C_EventControllerScrollDecelerateCallback.

scroll

type C_EventControllerScrollScrollCallback = Ptr () -> CDouble -> CDouble -> Ptr () -> IO CInt

Type for the callback on the (unwrapped) C side.

type EventControllerScrollScrollCallback

Arguments

 = Double

dx: X delta

-> Double

dy: Y delta

-> IO Bool

Returns: True if the scroll event was handled, False otherwise.

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

afterEventControllerScrollScroll :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollScrollCallback -> m SignalHandlerId

Connect a signal handler for the scroll signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after eventControllerScroll #scroll callback

genClosure_EventControllerScrollScroll :: MonadIO m => EventControllerScrollScrollCallback -> m (GClosure C_EventControllerScrollScrollCallback)

Wrap the callback into a GClosure.

mk_EventControllerScrollScrollCallback :: C_EventControllerScrollScrollCallback -> IO (FunPtr C_EventControllerScrollScrollCallback)

Generate a function pointer callable from C code, from a C_EventControllerScrollScrollCallback.

noEventControllerScrollScrollCallback :: Maybe EventControllerScrollScrollCallback

A convenience synonym for Nothing :: Maybe EventControllerScrollScrollCallback.

onEventControllerScrollScroll :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollScrollCallback -> m SignalHandlerId

Connect a signal handler for the scroll signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on eventControllerScroll #scroll callback

wrap_EventControllerScrollScrollCallback :: EventControllerScrollScrollCallback -> C_EventControllerScrollScrollCallback

Wrap a EventControllerScrollScrollCallback into a C_EventControllerScrollScrollCallback.

scrollBegin

type C_EventControllerScrollScrollBeginCallback = Ptr () -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type EventControllerScrollScrollBeginCallback = IO ()

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

afterEventControllerScrollScrollBegin :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollScrollBeginCallback -> m SignalHandlerId

Connect a signal handler for the scrollBegin signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after eventControllerScroll #scrollBegin callback

genClosure_EventControllerScrollScrollBegin :: MonadIO m => EventControllerScrollScrollBeginCallback -> m (GClosure C_EventControllerScrollScrollBeginCallback)

Wrap the callback into a GClosure.

mk_EventControllerScrollScrollBeginCallback :: C_EventControllerScrollScrollBeginCallback -> IO (FunPtr C_EventControllerScrollScrollBeginCallback)

Generate a function pointer callable from C code, from a C_EventControllerScrollScrollBeginCallback.

noEventControllerScrollScrollBeginCallback :: Maybe EventControllerScrollScrollBeginCallback

A convenience synonym for Nothing :: Maybe EventControllerScrollScrollBeginCallback.

onEventControllerScrollScrollBegin :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollScrollBeginCallback -> m SignalHandlerId

Connect a signal handler for the scrollBegin signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on eventControllerScroll #scrollBegin callback

wrap_EventControllerScrollScrollBeginCallback :: EventControllerScrollScrollBeginCallback -> C_EventControllerScrollScrollBeginCallback

Wrap a EventControllerScrollScrollBeginCallback into a C_EventControllerScrollScrollBeginCallback.

scrollEnd

type C_EventControllerScrollScrollEndCallback = Ptr () -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type EventControllerScrollScrollEndCallback = IO ()

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

afterEventControllerScrollScrollEnd :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollScrollEndCallback -> m SignalHandlerId

Connect a signal handler for the scrollEnd signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after eventControllerScroll #scrollEnd callback

genClosure_EventControllerScrollScrollEnd :: MonadIO m => EventControllerScrollScrollEndCallback -> m (GClosure C_EventControllerScrollScrollEndCallback)

Wrap the callback into a GClosure.

mk_EventControllerScrollScrollEndCallback :: C_EventControllerScrollScrollEndCallback -> IO (FunPtr C_EventControllerScrollScrollEndCallback)

Generate a function pointer callable from C code, from a C_EventControllerScrollScrollEndCallback.

noEventControllerScrollScrollEndCallback :: Maybe EventControllerScrollScrollEndCallback

A convenience synonym for Nothing :: Maybe EventControllerScrollScrollEndCallback.

onEventControllerScrollScrollEnd :: (IsEventControllerScroll a, MonadIO m) => a -> EventControllerScrollScrollEndCallback -> m SignalHandlerId

Connect a signal handler for the scrollEnd signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on eventControllerScroll #scrollEnd callback

wrap_EventControllerScrollScrollEndCallback :: EventControllerScrollScrollEndCallback -> C_EventControllerScrollScrollEndCallback

Wrap a EventControllerScrollScrollEndCallback into a C_EventControllerScrollScrollEndCallback.