GI.Gdk.Objects.Display

Display objects purpose are two fold:

• To manage and provide information about input devices (pointers and keyboards)
• To manage and provide information about the available GdkScreens

GdkDisplay objects are the GDK representation of an X Display, which can be described as a workstation consisting of a keyboard, a pointing device (such as a mouse) and one or more screens. It is used to open and keep track of various GdkScreen objects currently instantiated by the application. It is also used to access the keyboard(s) and mouse pointer(s) of the display.

Most of the input device handling has been factored out into the separate DeviceManager object. Every display has a device manager, which you can obtain using displayGetDeviceManager.

Exported types

newtype Display

Memory-managed wrapper type.

Constructors

Display (ManagedPtr Display)

Instances

Eq Display

Defined in GI.Gdk.Objects.Display

Methods

(==) :: Display -> Display -> Bool

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

GObject Display

Defined in GI.Gdk.Objects.Display

ManagedPtrNewtype Display

Defined in GI.Gdk.Objects.Display

Methods

toManagedPtr :: Display -> ManagedPtr Display

TypedObject Display

Defined in GI.Gdk.Objects.Display

Methods

glibType :: IO GType

HasParentTypes Display

Defined in GI.Gdk.Objects.Display

IsGValue (Maybe Display)

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

Defined in GI.Gdk.Objects.Display

Methods

gvalueGType_ :: IO GType

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

gvalueGet_ :: Ptr GValue -> IO (Maybe Display)

type ParentTypes Display

Defined in GI.Gdk.Objects.Display

type ParentTypes Display = '[Object]

class (GObject o, IsDescendantOf Display o) => IsDisplay o

Type class for types which can be safely cast to Display, for instance with toDisplay.

Instances

(GObject o, IsDescendantOf Display o) => IsDisplay o

Defined in GI.Gdk.Objects.Display

toDisplay :: (MonadIO m, IsDisplay o) => o -> m Display

Cast to Display, 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

beep, bindProperty, bindPropertyFull, close, deviceIsGrabbed, flush, forceFloating, freezeNotify, getv, hasPending, isClosed, isFloating, keyboardUngrab, listDevices, listSeats, notify, notifyByPspec, notifyStartupComplete, peekEvent, pointerIsGrabbed, pointerUngrab, putEvent, ref, refSink, requestSelectionNotification, runDispose, stealData, stealQdata, storeClipboard, supportsClipboardPersistence, supportsComposite, supportsCursorAlpha, supportsCursorColor, supportsInputShapes, supportsSelectionNotification, supportsShapes, sync, thawNotify, unref, warpPointer, watchClosure.

Getters

getAppLaunchContext, getData, getDefaultCursorSize, getDefaultGroup, getDefaultScreen, getDefaultSeat, getDeviceManager, getEvent, getMaximalCursorSize, getMonitor, getMonitorAtPoint, getMonitorAtWindow, getNMonitors, getNScreens, getName, getPointer, getPrimaryMonitor, getProperty, getQdata, getScreen, getWindowAtPointer.

Setters

setData, setDataFull, setDoubleClickDistance, setDoubleClickTime, setProperty.

beep

displayBeep

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m ()

Emits a short beep on display

Since: 2.2

close

displayClose

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m ()

Closes the connection to the windowing system for the given display, and cleans up associated resources.

Since: 2.2

deviceIsGrabbed

displayDeviceIsGrabbed

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a, IsDevice b)

=> a

display: a Display

-> b

device: a Device

-> m Bool

Returns: True if there is a grab in effect for device.

Returns True if there is an ongoing grab on device for display.

flush

displayFlush

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m ()

Flushes any requests queued for the windowing system; this happens automatically when the main loop blocks waiting for new events, but if your application is drawing without returning control to the main loop, you may need to call this function explicitly. A common case where this function needs to be called is when an application is executing drawing commands from a thread other than the thread where the main loop is running.

This is most useful for X11. On windowing systems where requests are handled synchronously, this function will do nothing.

Since: 2.4

getAppLaunchContext

displayGetAppLaunchContext

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m AppLaunchContext

Returns: a new AppLaunchContext for display. Free with objectUnref when done

Returns a AppLaunchContext suitable for launching applications on the given display.

Since: 3.0

getDefault

displayGetDefault

Arguments

:: (HasCallStack, MonadIO m)

=> m (Maybe Display)

Returns: a Display, or Nothing if there is no default display.

Gets the default Display. This is a convenience function for: gdk_display_manager_get_default_display (gdk_display_manager_get ()).

Since: 2.2

getDefaultCursorSize

displayGetDefaultCursorSize

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Word32

Returns: the default cursor size.

Returns the default size to use for cursors on display.

Since: 2.4

getDefaultGroup

displayGetDefaultGroup

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Window

Returns: The default group leader window for display

Returns the default group leader window for all toplevel windows on display. This window is implicitly created by GDK. See windowSetGroup.

Since: 2.4

getDefaultScreen

displayGetDefaultScreen

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Screen

Returns: the default Screen object for display

Get the default Screen for display.

Since: 2.2

getDefaultSeat

displayGetDefaultSeat

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Seat

Returns: the default seat.

Returns the default Seat for this display.

Since: 3.20

getDeviceManager

displayGetDeviceManager

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display.

-> m (Maybe DeviceManager)

Returns: A DeviceManager, or Nothing. This memory is owned by GDK and must not be freed or unreferenced.

Deprecated: (Since version 3.20.)Use displayGetDefaultSeat and Seat operations.

Returns the DeviceManager associated to display.

Since: 3.0

getEvent

displayGetEvent

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m (Maybe Event)

Returns: the next Event to be processed, or Nothing if no events are pending. The returned Event should be freed with eventFree.

Gets the next Event to be processed for display, fetching events from the windowing system if necessary.

Since: 2.2

getMaximalCursorSize

displayGetMaximalCursorSize

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m (Word32, Word32)

Gets the maximal size to use for cursors on display.

Since: 2.4

getMonitor

displayGetMonitor

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Int32

monitorNum: number of the monitor

-> m (Maybe Monitor)

Returns: the Monitor, or Nothing if monitorNum is not a valid monitor number

Gets a monitor associated with this display.

Since: 3.22

getMonitorAtPoint

displayGetMonitorAtPoint

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Int32

x: the x coordinate of the point

-> Int32

y: the y coordinate of the point

-> m Monitor

Returns: the monitor containing the point

Gets the monitor in which the point (x, y) is located, or a nearby monitor if the point is not in any monitor.

Since: 3.22

getMonitorAtWindow

displayGetMonitorAtWindow

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a, IsWindow b)

=> a

display: a Display

-> b

window: a Window

-> m Monitor

Returns: the monitor with the largest overlap with window

Gets the monitor in which the largest area of window resides, or a monitor close to window if it is outside of all monitors.

Since: 3.22

getNMonitors

displayGetNMonitors

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Int32

Returns: the number of monitors

Gets the number of monitors that belong to display.

The returned number is valid until the next emission of the monitorAdded or monitorRemoved signal.

Since: 3.22

getNScreens

displayGetNScreens

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Int32

Returns: number of screens.

Deprecated: (Since version 3.10)The number of screens is always 1.

Gets the number of screen managed by the display.

Since: 2.2

getName

displayGetName

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Text

Returns: a string representing the display name. This string is owned by GDK and should not be modified or freed.

Gets the name of the display.

Since: 2.2

getPointer

displayGetPointer

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m (Screen, Int32, Int32, [ModifierType])

Deprecated: (Since version 3.0)Use deviceGetPosition instead.

Gets the current location of the pointer and the current modifier mask for a given display.

Since: 2.2

getPrimaryMonitor

displayGetPrimaryMonitor

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m (Maybe Monitor)

Returns: the primary monitor, or Nothing if no primary monitor is configured by the user

Gets the primary monitor for the display.

The primary monitor is considered the monitor where the “main desktop” lives. While normal application windows typically allow the window manager to place the windows, specialized desktop applications such as panels should place themselves on the primary monitor.

Since: 3.22

getScreen

displayGetScreen

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Int32

screenNum: the screen number

-> m Screen

Returns: the Screen object

Deprecated: (Since version 3.20)There is only one screen; use displayGetDefaultScreen to get it.

Returns a screen object for one of the screens of the display.

Since: 2.2

getWindowAtPointer

displayGetWindowAtPointer

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m (Maybe Window, Int32, Int32)

Returns: the window under the mouse pointer, or Nothing

Deprecated: (Since version 3.0)Use deviceGetWindowAtPosition instead.

Obtains the window underneath the mouse pointer, returning the location of the pointer in that window in winX, winY for screen. Returns Nothing if the window under the mouse pointer is not known to GDK (for example, belongs to another application).

Since: 2.2

hasPending

displayHasPending

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: True if there are events ready to be processed.

Returns whether the display has events that are waiting to be processed.

Since: 3.0

isClosed

displayIsClosed

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: True if the display is closed.

Finds out if the display has been closed.

Since: 2.22

keyboardUngrab

displayKeyboardUngrab

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display.

-> Word32

time_: a timestap (e.g CURRENT_TIME).

-> m ()

Deprecated: (Since version 3.0)Use deviceUngrab, together with deviceGrab instead.

Release any keyboard grab

Since: 2.2

listDevices

displayListDevices

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m [Device]

Returns: a list of Device

Deprecated: (Since version 3.0)Use deviceManagerListDevices instead.

Returns the list of available input devices attached to display. The list is statically allocated and should not be freed.

Since: 2.2

listSeats

displayListSeats

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m [Seat]

Returns: the list of seats known to the Display

Returns the list of seats known to display.

Since: 3.20

notifyStartupComplete

displayNotifyStartupComplete

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Text

startupId: a startup-notification identifier, for which notification process should be completed

-> m ()

Indicates to the GUI environment that the application has finished loading, using a given identifier.

GTK+ will call this function automatically for GtkWindow with custom startup-notification identifier unless gtk_window_set_auto_startup_notification() is called to disable that feature.

Since: 3.0

open

displayOpen

Arguments

:: (HasCallStack, MonadIO m)

=> Text

displayName: the name of the display to open

-> m (Maybe Display)

Returns: a Display, or Nothing if the display could not be opened

Opens a display.

Since: 2.2

openDefaultLibgtkOnly

displayOpenDefaultLibgtkOnly

Arguments

:: (HasCallStack, MonadIO m)

=> m (Maybe Display)

Returns: the default display, if it could be opened, otherwise Nothing.

Deprecated: (Since version 3.16)This symbol was never meant to be used outside of GTK+

Opens the default display specified by command line arguments or environment variables, sets it as the default display, and returns it. parseArgs must have been called first. If the default display has previously been set, simply returns that. An internal function that should not be used by applications.

peekEvent

displayPeekEvent

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m (Maybe Event)

Returns: a copy of the first Event on the event queue, or Nothing if no events are in the queue. The returned Event should be freed with eventFree.

Gets a copy of the first Event in the display’s event queue, without removing the event from the queue. (Note that this function will not get more events from the windowing system. It only checks the events that have already been moved to the GDK event queue.)

Since: 2.2

pointerIsGrabbed

displayPointerIsGrabbed

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: True if an active X pointer grab is in effect

Deprecated: (Since version 3.0)Use displayDeviceIsGrabbed instead.

Test if the pointer is grabbed.

Since: 2.2

pointerUngrab

displayPointerUngrab

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display.

-> Word32

time_: a timestap (e.g. CURRENT_TIME).

-> m ()

Deprecated: (Since version 3.0)Use deviceUngrab, together with deviceGrab instead.

Release any pointer grab.

Since: 2.2

putEvent

displayPutEvent

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Event

event: a Event.

-> m ()

Appends a copy of the given event onto the front of the event queue for display.

Since: 2.2

requestSelectionNotification

displayRequestSelectionNotification

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Atom

selection: the Atom naming the selection for which ownership change notification is requested

-> m Bool

Returns: whether EventOwnerChange events will be sent.

Request EventOwnerChange events for ownership changes of the selection named by the given atom.

Since: 2.6

setDoubleClickDistance

displaySetDoubleClickDistance

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Word32

distance: distance in pixels

-> m ()

Sets the double click distance (two clicks within this distance count as a double click and result in a GDK_2BUTTON_PRESS event). See also displaySetDoubleClickTime. Applications should not set this, it is a global user-configured setting.

Since: 2.4

setDoubleClickTime

displaySetDoubleClickTime

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> Word32

msec: double click time in milliseconds (thousandths of a second)

-> m ()

Sets the double click time (two clicks within this time interval count as a double click and result in a GDK_2BUTTON_PRESS event). Applications should not set this, it is a global user-configured setting.

Since: 2.2

storeClipboard

displayStoreClipboard

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a, IsWindow b)

=> a

display: a Display

-> b

clipboardWindow: a Window belonging to the clipboard owner

-> Word32

time_: a timestamp

-> Maybe [Atom]

targets: an array of targets that should be saved, or Nothing if all available targets should be saved.

-> m ()

Issues a request to the clipboard manager to store the clipboard data. On X11, this is a special program that works according to the FreeDesktop Clipboard Specification.

Since: 2.6

supportsClipboardPersistence

displaySupportsClipboardPersistence

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: True if the display supports clipboard persistance.

Returns whether the speicifed display supports clipboard persistance; i.e. if it’s possible to store the clipboard data after an application has quit. On X11 this checks if a clipboard daemon is running.

Since: 2.6

supportsComposite

displaySupportsComposite

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: True if windows may be composited.

Deprecated: (Since version 3.16)Compositing is an outdated technology that only ever worked on X11.

Returns True if windowSetComposited can be used to redirect drawing on the window using compositing.

Currently this only works on X11 with XComposite and XDamage extensions available.

Since: 2.12

supportsCursorAlpha

displaySupportsCursorAlpha

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: whether cursors can have alpha channels.

Returns True if cursors can use an 8bit alpha channel on display. Otherwise, cursors are restricted to bilevel alpha (i.e. a mask).

Since: 2.4

supportsCursorColor

displaySupportsCursorColor

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: whether cursors can have multiple colors.

Returns True if multicolored cursors are supported on display. Otherwise, cursors have only a forground and a background color.

Since: 2.4

supportsInputShapes

displaySupportsInputShapes

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: True if windows with modified input shape are supported

Returns True if gdk_window_input_shape_combine_mask() can be used to modify the input shape of windows on display.

Since: 2.10

supportsSelectionNotification

displaySupportsSelectionNotification

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: whether EventOwnerChange events will be sent.

Returns whether EventOwnerChange events will be sent when the owner of a selection changes.

Since: 2.6

supportsShapes

displaySupportsShapes

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m Bool

Returns: True if shaped windows are supported

Returns True if gdk_window_shape_combine_mask() can be used to create shaped windows on display.

Since: 2.10

sync

displaySync

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a)

=> a

display: a Display

-> m ()

Flushes any requests queued for the windowing system and waits until all requests have been handled. This is often used for making sure that the display is synchronized with the current state of the program. Calling displaySync before errorTrapPop makes sure that any errors generated from earlier requests are handled before the error trap is removed.

This is most useful for X11. On windowing systems where requests are handled synchronously, this function will do nothing.

Since: 2.2

warpPointer

displayWarpPointer

Arguments

:: (HasCallStack, MonadIO m, IsDisplay a, IsScreen b)

=> a

display: a Display

-> b

screen: the screen of display to warp the pointer to

-> Int32

x: the x coordinate of the destination

-> Int32

y: the y coordinate of the destination

-> m ()

Deprecated: (Since version 3.0)Use deviceWarp instead.

Warps the pointer of display to the point x,y on the screen screen, unless the pointer is confined to a window by a grab, in which case it will be moved as far as allowed by the grab. Warping the pointer creates events as if the user had moved the mouse instantaneously to the destination.

Note that the pointer should normally be under the control of the user. This function was added to cover some rare use cases like keyboard navigation support for the color picker in the GtkColorSelectionDialog.

Since: 2.8

Signals

closed

type DisplayClosedCallback

Arguments

 = Bool

isError: True if the display was closed due to an error

-> IO ()

The closed signal is emitted when the connection to the windowing system for display is closed.

Since: 2.2

afterDisplayClosed :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayClosedCallback) -> m SignalHandlerId

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

after display #closed 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.

onDisplayClosed :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayClosedCallback) -> m SignalHandlerId

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

on display #closed callback

monitorAdded

type DisplayMonitorAddedCallback

Arguments

 = Monitor

monitor: the monitor that was just added

-> IO ()

The monitorAdded signal is emitted whenever a monitor is added.

Since: 3.22

afterDisplayMonitorAdded :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayMonitorAddedCallback) -> m SignalHandlerId

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

after display #monitorAdded 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.

onDisplayMonitorAdded :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayMonitorAddedCallback) -> m SignalHandlerId

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

on display #monitorAdded callback

monitorRemoved

type DisplayMonitorRemovedCallback

Arguments

 = Monitor

monitor: the monitor that was just removed

-> IO ()

The monitorRemoved signal is emitted whenever a monitor is removed.

Since: 3.22

afterDisplayMonitorRemoved :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayMonitorRemovedCallback) -> m SignalHandlerId

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

after display #monitorRemoved 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.

onDisplayMonitorRemoved :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayMonitorRemovedCallback) -> m SignalHandlerId

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

on display #monitorRemoved callback

opened

type DisplayOpenedCallback = IO ()

The opened signal is emitted when the connection to the windowing system for display is opened.

afterDisplayOpened :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayOpenedCallback) -> m SignalHandlerId

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

after display #opened 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.

onDisplayOpened :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplayOpenedCallback) -> m SignalHandlerId

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

on display #opened callback

seatAdded

type DisplaySeatAddedCallback

Arguments

 = Seat

seat: the seat that was just added

-> IO ()

The seatAdded signal is emitted whenever a new seat is made known to the windowing system.

Since: 3.20

afterDisplaySeatAdded :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplaySeatAddedCallback) -> m SignalHandlerId

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

after display #seatAdded 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.

onDisplaySeatAdded :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplaySeatAddedCallback) -> m SignalHandlerId

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

on display #seatAdded callback

seatRemoved

type DisplaySeatRemovedCallback

Arguments

 = Seat

seat: the seat that was just removed

-> IO ()

The seatRemoved signal is emitted whenever a seat is removed by the windowing system.

Since: 3.20

afterDisplaySeatRemoved :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplaySeatRemovedCallback) -> m SignalHandlerId

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

after display #seatRemoved 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.

onDisplaySeatRemoved :: (IsDisplay a, MonadIO m) => a -> ((?self :: a) => DisplaySeatRemovedCallback) -> m SignalHandlerId

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

on display #seatRemoved callback