GI.Gtk.Objects.EventControllerScroll

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

In the case of continuous scroll events, GtkEventControllerScroll encloses all EventControllerScroll::scroll emissions between two EventControllerScroll::scrollBegin and EventControllerScroll::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 EventControllerScrollFlagsVertical, EventControllerScrollFlagsHorizontal and EventControllerScrollFlagsBothAxes. If any axis is disabled, the respective 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 EventControllerScrollFlagsDiscrete. This can be used to implement discrete actions triggered through scroll events (e.g. switching across combobox options).

The EventControllerScrollFlagsKinetic flag toggles the emission of the EventControllerScroll::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

GObject EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

ManagedPtrNewtype EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

Methods

toManagedPtr :: EventControllerScroll -> ManagedPtr EventControllerScroll

TypedObject EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

Methods

glibType :: IO GType

HasParentTypes EventControllerScroll

Defined in GI.Gtk.Objects.EventControllerScroll

IsGValue (Maybe EventControllerScroll)

Convert EventControllerScroll to and from GValue. See toGValue and fromGValue.

Defined in GI.Gtk.Objects.EventControllerScroll

Methods

gvalueGType_ :: IO GType

gvalueSet_ :: Ptr GValue -> Maybe EventControllerScroll -> IO ()

gvalueGet_ :: Ptr GValue -> IO (Maybe 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.

Methods

Click to display all available methods, including inherited ones

Methods

bindProperty, bindPropertyFull, forceFloating, freezeNotify, getv, isFloating, notify, notifyByPspec, ref, refSink, reset, runDispose, stealData, stealQdata, thawNotify, unref, watchClosure.

Getters

getCurrentEvent, getCurrentEventDevice, getCurrentEventState, getCurrentEventTime, getData, getFlags, getName, getPropagationLimit, getPropagationPhase, getProperty, getQdata, getUnit, getWidget.

Setters

setData, setDataFull, setFlags, setName, setPropagationLimit, setPropagationPhase, setProperty, setStaticName.

getFlags

eventControllerScrollGetFlags

Arguments

:: (HasCallStack, MonadIO m, IsEventControllerScroll a)

=> a

scroll: a GtkEventControllerScroll

-> m [EventControllerScrollFlags]

Returns: the controller flags.

Gets the flags conditioning the scroll controller behavior.

getUnit

eventControllerScrollGetUnit

Arguments

:: (HasCallStack, MonadIO m, IsEventControllerScroll a)

=> a

scroll: a GtkEventControllerScroll.

-> m ScrollUnit

Returns: the scroll unit.

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

Always returns ScrollUnitWheel if the EventControllerScrollFlagsDiscrete flag is set.

Since: 4.8

new

eventControllerScrollNew

Arguments

:: (HasCallStack, MonadIO m)

=> [EventControllerScrollFlags]

flags: flags affecting the controller behavior

-> m EventControllerScroll

Returns: a new GtkEventControllerScroll

Creates a new event controller that will handle scroll events.

setFlags

eventControllerScrollSetFlags

Arguments

:: (HasCallStack, MonadIO m, IsEventControllerScroll a)

=> a

scroll: a GtkEventControllerScroll

-> [EventControllerScrollFlags]

flags: flags affecting the controller behavior

-> m ()

Sets the flags conditioning scroll controller behavior.

Properties

flags

The flags affecting event controller behavior.

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

Arguments

 = Double

velX: X velocity

-> Double

velY: Y velocity

-> IO ()

Emitted after scroll is finished if the EventControllerScrollFlagsKinetic 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 -> ((?self :: 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

By default the object invoking the signal is not passed to the callback. If you need to access it, you can use the implit ?self parameter. Note that this requires activating the ImplicitParams GHC extension.

onEventControllerScrollDecelerate :: (IsEventControllerScroll a, MonadIO m) => a -> ((?self :: 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

scroll

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.

For the representation unit of the deltas, see eventControllerScrollGetUnit.

afterEventControllerScrollScroll :: (IsEventControllerScroll a, MonadIO m) => a -> ((?self :: 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

By default the object invoking the signal is not passed to the callback. If you need to access it, you can use the implit ?self parameter. Note that this requires activating the ImplicitParams GHC extension.

onEventControllerScrollScroll :: (IsEventControllerScroll a, MonadIO m) => a -> ((?self :: 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

scrollBegin

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 -> ((?self :: 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

By default the object invoking the signal is not passed to the callback. If you need to access it, you can use the implit ?self parameter. Note that this requires activating the ImplicitParams GHC extension.

onEventControllerScrollScrollBegin :: (IsEventControllerScroll a, MonadIO m) => a -> ((?self :: 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

scrollEnd

type EventControllerScrollScrollEndCallback = IO ()

Signals that a scrolling operation has finished.

It will only be emitted on devices capable of it.

afterEventControllerScrollScrollEnd :: (IsEventControllerScroll a, MonadIO m) => a -> ((?self :: 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

By default the object invoking the signal is not passed to the callback. If you need to access it, you can use the implit ?self parameter. Note that this requires activating the ImplicitParams GHC extension.

onEventControllerScrollScrollEnd :: (IsEventControllerScroll a, MonadIO m) => a -> ((?self :: 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