gtkmm: Gdk::Display Class Reference

Gdk::Display object's purpose is two fold: To grab/ungrab keyboard focus and mouse pointer To manage and provide information about the Gdk::Monitor(s) available for this Gdk::Display. More...

#include <gdkmm/display.h>

Inheritance diagram for Gdk::Display:

[legend]

Public Member Functions
	Display (Display && src) noexcept

Display &	operator= (Display && src) noexcept

	~Display () noexcept override

GdkDisplay *	gobj ()
	Provides access to the underlying C GObject.

const GdkDisplay *	gobj () const
	Provides access to the underlying C GObject.

GdkDisplay *	gobj_copy ()
	Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

Glib::ustring	get_name () const
	Gets the name of the display.

bool	device_is_grabbed (const Glib::RefPtr< const Gdk::Device > & device) const
	Returns `true` if there is an ongoing grab on device for display.

void	beep ()
	Emits a short beep on display.

void	sync ()
	Flushes any requests queued for the windowing system and waits until all requests have been handled.

void	close ()
	Closes the connection to the windowing system for the given display.

bool	is_closed () const
	Finds out if the display has been closed.

bool	is_composited () const
	Returns whether surfaces can reasonably be expected to have their alpha channel drawn correctly on the screen.

bool	is_rgba () const
	Returns whether surfaces on this display are created with an alpha channel.

bool	supports_shadow_width () const
	Returns whether it's possible for a surface to draw outside of the window area.

void	put_event (const Glib::RefPtr< const Event > & event)
	Adds the given event to the event queue for display.

void	flush ()
	Flushes any requests queued for the windowing system.

Glib::RefPtr< Clipboard >	get_clipboard ()
	Gets the clipboard used for copy/paste operations.

Glib::RefPtr< const Clipboard >	get_clipboard () const
	Gets the clipboard used for copy/paste operations.

Glib::RefPtr< Clipboard >	get_primary_clipboard ()
	Gets the clipboard used for the primary selection.

Glib::RefPtr< const Clipboard >	get_primary_clipboard () const
	Gets the clipboard used for the primary selection.

bool	supports_input_shapes () const
	Returns `true` if the display supports input shapes.

void	prepare_gl ()
	Checks that OpenGL is available for this display and ensures that it is properly initialized.

Glib::RefPtr< GLContext >	create_gl_context ()
	Creates a new `Gdk::GLContext` for the `Gdk::Display`.

void	notify_startup_complete (const Glib::ustring & startup_id)
	Indicates to the GUI environment that the application has finished loading, using a given identifier.

Glib::ustring	get_startup_notification_id () const
	Gets the startup notification ID for a Wayland display, or `nullptr` if no ID has been defined.

Glib::RefPtr< AppLaunchContext >	get_app_launch_context ()
	Returns a `Gdk::AppLaunchContext` suitable for launching applications on the given display.

Glib::RefPtr< const AppLaunchContext >	get_app_launch_context () const
	Returns a `Gdk::AppLaunchContext` suitable for launching applications on the given display.

Glib::RefPtr< Seat >	get_default_seat ()
	Returns the default `Gdk::Seat` for this display.

Glib::RefPtr< const Seat >	get_default_seat () const
	Returns the default `Gdk::Seat` for this display.

std::vector< Glib::RefPtr< Seat > >	list_seats ()
	Returns the list of seats known to display.

std::vector< Glib::RefPtr< const Seat > >	list_seats () const
	Returns the list of seats known to display.

Glib::RefPtr< Gio::ListModel >	get_monitors ()
	Gets the list of monitors associated with this display.

Glib::RefPtr< const Gio::ListModel >	get_monitors () const
	Gets the list of monitors associated with this display.

Glib::RefPtr< Monitor >	get_monitor_at_surface (const Glib::RefPtr< Surface > & surface)
	Gets the monitor in which the largest area of surface resides.

Glib::RefPtr< const Monitor >	get_monitor_at_surface (const Glib::RefPtr< Surface > & surface) const
	Gets the monitor in which the largest area of surface resides.

template<class ValueType >
bool	get_setting (const Glib::ustring & name, ValueType & value) const

Glib::RefPtr< DmabufFormats >	get_dmabuf_formats ()
	Returns the dma-buf formats that are supported on this display.

Glib::RefPtr< const DmabufFormats >	get_dmabuf_formats () const
	Returns the dma-buf formats that are supported on this display.

Glib::SignalProxy< void(bool)>	signal_closed ()

Glib::SignalProxy< void()>	signal_opened ()

Glib::SignalProxy< void(const Glib::RefPtr< Seat > &)>	signal_seat_added ()

Glib::SignalProxy< void(const Glib::RefPtr< Seat > &)>	signal_seat_removed ()

Glib::SignalProxy< void(const Glib::ustring &)>	signal_setting_changed ()

Glib::PropertyProxy_ReadOnly< bool >	property_composited () const
	`true` if the display properly composites the alpha channel.

Glib::PropertyProxy_ReadOnly< bool >	property_rgba () const
	`true` if the display supports an alpha channel.

Glib::PropertyProxy_ReadOnly< bool >	property_shadow_width () const
	`true` if the display supports extensible frames.

Glib::PropertyProxy_ReadOnly< bool >	property_input_shapes () const
	`true` if the display supports input shapes.

Glib::PropertyProxy_ReadOnly< Glib::RefPtr< DmabufFormats > >	property_dmabuf_formats () const
	The dma-buf formats that are supported on this display.

Static Public Member Functions
static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system.

static Glib::RefPtr< Display >	open (const Glib::ustring & display_name)
	Opens a display.

static Glib::RefPtr< Display >	get_default ()
	Gets the default `Gdk::Display`.

Protected Member Functions
	Display ()

Related Symbols
(Note that these are not member symbols.)
Glib::RefPtr< Gdk::Display >	wrap (GdkDisplay * object, bool take_copy=false)
	A Glib::wrap() method for this object.

Detailed Description

Gdk::Display object's purpose is two fold: To grab/ungrab keyboard focus and mouse pointer To manage and provide information about the Gdk::Monitor(s) available for this Gdk::Display.

Gdk::Display objects are the GDK representation of the 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 Gdk::Monitor objects currently instantiated by the application. It is also used to grab and release the keyboard and the mouse pointer.

Constructor & Destructor Documentation

◆ Display() [1/2]

Gdk::Display::Display ( Display && src )

noexcept

◆ ~Display()

Gdk::Display::~Display ( )

overridenoexcept

◆ Display() [2/2]

Gdk::Display::Display ( )

protected

Member Function Documentation

◆ beep()

void Gdk::Display::beep ( )

Emits a short beep on display.

◆ close()

void Gdk::Display::close ( )

Closes the connection to the windowing system for the given display.

This cleans up associated resources.

◆ create_gl_context()

Glib::RefPtr< GLContext > Gdk::Display::create_gl_context ( )

Creates a new Gdk::GLContext for the Gdk::Display.

The context is disconnected from any particular surface or surface and cannot be used to draw to any surface. It can only be used to draw to non-surface framebuffers like textures.

If the creation of the Gdk::GLContext failed, error will be set. Before using the returned Gdk::GLContext, you will need to call Gdk::GLContext::make_current() or Gdk::GLContext::realize().

Since gtkmm 4.6:

Returns: The newly created Gdk::GLContext.

Exceptions

Glib::Error

◆ device_is_grabbed()

bool Gdk::Display::device_is_grabbed ( const Glib::RefPtr< const Gdk::Device > & device ) const

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

Parameters

device A Gdk::Device.

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

◆ flush()

void Gdk::Display::flush ( )

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.

◆ get_app_launch_context() [1/2]

Glib::RefPtr< AppLaunchContext > Gdk::Display::get_app_launch_context ( )

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

Returns: A new Gdk::AppLaunchContext for display.

◆ get_app_launch_context() [2/2]

Glib::RefPtr< const AppLaunchContext > Gdk::Display::get_app_launch_context ( ) const

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

Returns: A new Gdk::AppLaunchContext for display.

◆ get_clipboard() [1/2]

Glib::RefPtr< Clipboard > Gdk::Display::get_clipboard ( )

Gets the clipboard used for copy/paste operations.

Returns: The display's clipboard.

◆ get_clipboard() [2/2]

Glib::RefPtr< const Clipboard > Gdk::Display::get_clipboard ( ) const

Gets the clipboard used for copy/paste operations.

Returns: The display's clipboard.

◆ get_default()

static Glib::RefPtr< Display > Gdk::Display::get_default ( )

static

Gets the default Gdk::Display.

This is a convenience function for:

gdk_display_manager_get_default_display (Gdk::DisplayManager::get())

Returns: A Gdk::Display, or nullptr if there is no default display.

◆ get_default_seat() [1/2]

Glib::RefPtr< Seat > Gdk::Display::get_default_seat ( )

Returns the default Gdk::Seat for this display.

Note that a display may not have a seat. In this case, this function will return nullptr.

Returns: The default seat.

◆ get_default_seat() [2/2]

Glib::RefPtr< const Seat > Gdk::Display::get_default_seat ( ) const

Returns the default Gdk::Seat for this display.

Note that a display may not have a seat. In this case, this function will return nullptr.

Returns: The default seat.

◆ get_dmabuf_formats() [1/2]

Glib::RefPtr< DmabufFormats > Gdk::Display::get_dmabuf_formats ( )

Returns the dma-buf formats that are supported on this display.

GTK may use OpenGL or Vulkan to support some formats. Calling this function will then initialize them if they aren't yet.

The formats returned by this function can be used for negotiating buffer formats with producers such as v4l, pipewire or GStreamer.

To learn more about dma-bufs, see Gdk::DmabufTextureBuilder.

Since gtkmm 4.14:

Returns: A Gdk::DmabufFormats object.

◆ get_dmabuf_formats() [2/2]

Glib::RefPtr< const DmabufFormats > Gdk::Display::get_dmabuf_formats ( ) const

Returns the dma-buf formats that are supported on this display.

GTK may use OpenGL or Vulkan to support some formats. Calling this function will then initialize them if they aren't yet.

The formats returned by this function can be used for negotiating buffer formats with producers such as v4l, pipewire or GStreamer.

To learn more about dma-bufs, see Gdk::DmabufTextureBuilder.

Since gtkmm 4.14:

Returns: A Gdk::DmabufFormats object.

◆ get_monitor_at_surface() [1/2]

Glib::RefPtr< Monitor > Gdk::Display::get_monitor_at_surface ( const Glib::RefPtr< Surface > & surface )

Gets the monitor in which the largest area of surface resides.

Parameters

surface A Gdk::Surface.

Returns: The monitor with the largest overlap with surface.

◆ get_monitor_at_surface() [2/2]

Glib::RefPtr< const Monitor > Gdk::Display::get_monitor_at_surface ( const Glib::RefPtr< Surface > & surface ) const

Gets the monitor in which the largest area of surface resides.

Parameters

surface A Gdk::Surface.

Returns: The monitor with the largest overlap with surface.

◆ get_monitors() [1/2]

Glib::RefPtr< Gio::ListModel > Gdk::Display::get_monitors ( )

Gets the list of monitors associated with this display.

Subsequent calls to this function will always return the same list for the same display.

You can listen to the GListModel::items-changed signal on this list to monitor changes to the monitor of this display.

Returns: A Gio::ListModel of Gdk::Monitor.

◆ get_monitors() [2/2]

Glib::RefPtr< const Gio::ListModel > Gdk::Display::get_monitors ( ) const

Gets the list of monitors associated with this display.

Subsequent calls to this function will always return the same list for the same display.

You can listen to the GListModel::items-changed signal on this list to monitor changes to the monitor of this display.

Returns: A Gio::ListModel of Gdk::Monitor.

◆ get_name()

Glib::ustring Gdk::Display::get_name ( ) const

Gets the name of the display.

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

◆ get_primary_clipboard() [1/2]

Glib::RefPtr< Clipboard > Gdk::Display::get_primary_clipboard ( )

Gets the clipboard used for the primary selection.

On backends where the primary clipboard is not supported natively, GDK emulates this clipboard locally.

Returns: The primary clipboard.

◆ get_primary_clipboard() [2/2]

Glib::RefPtr< const Clipboard > Gdk::Display::get_primary_clipboard ( ) const

Gets the clipboard used for the primary selection.

On backends where the primary clipboard is not supported natively, GDK emulates this clipboard locally.

Returns: The primary clipboard.

◆ get_setting()

template <class ValueType >

bool Gdk::Display::get_setting	(	const Glib::ustring &	name,
		ValueType &	value
	)		const

◆ get_startup_notification_id()

Glib::ustring Gdk::Display::get_startup_notification_id ( ) const

Gets the startup notification ID for a Wayland display, or nullptr if no ID has been defined.

Deprecated: 4.10

Returns: The startup notification ID for display.

◆ get_type()

static GType Gdk::Display::get_type ( )

static

Get the GType for this class, for use with the underlying GObject type system.

◆ gobj() [1/2]

GdkDisplay * Gdk::Display::gobj ( )

inline

Provides access to the underlying C GObject.

◆ gobj() [2/2]

const GdkDisplay * Gdk::Display::gobj ( ) const

inline

Provides access to the underlying C GObject.

◆ gobj_copy()

GdkDisplay * Gdk::Display::gobj_copy ( )

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

◆ is_closed()

bool Gdk::Display::is_closed ( ) const

Finds out if the display has been closed.

Returns: true if the display is closed.

◆ is_composited()

bool Gdk::Display::is_composited ( ) const

Returns whether surfaces can reasonably be expected to have their alpha channel drawn correctly on the screen.

Check is_rgba() for whether the display supports an alpha channel.

On X11 this function returns whether a compositing manager is compositing on display.

On modern displays, this value is always true.

Returns: Whether surfaces with RGBA visuals can reasonably be expected to have their alpha channels drawn correctly on the screen.

◆ is_rgba()

bool Gdk::Display::is_rgba ( ) const

Returns whether surfaces on this display are created with an alpha channel.

Even if a true is returned, it is possible that the surface’s alpha channel won’t be honored when displaying the surface on the screen: in particular, for X an appropriate windowing manager and compositing manager must be running to provide appropriate display. Use is_composited() to check if that is the case.

On modern displays, this value is always true.

Returns: true if surfaces are created with an alpha channel or false if the display does not support this functionality.

◆ list_seats() [1/2]

std::vector< Glib::RefPtr< Seat > > Gdk::Display::list_seats ( )

Returns the list of seats known to display.

Returns: The list of seats known to the Gdk::Display.

◆ list_seats() [2/2]

std::vector< Glib::RefPtr< const Seat > > Gdk::Display::list_seats ( ) const

Returns the list of seats known to display.

Returns: The list of seats known to the Gdk::Display.

◆ notify_startup_complete()

void Gdk::Display::notify_startup_complete ( const Glib::ustring & startup_id )

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.

Deprecated: 4.10: Using Gdk::Toplevel::set_startup_id() is sufficient

Deprecated:: Using Gdk::Toplevel::set_startup_id() is sufficient.

Parameters

startup_id A startup-notification identifier, for which notification process should be completed.

◆ open()

static Glib::RefPtr< Display > Gdk::Display::open ( const Glib::ustring & display_name )

static

Opens a display.

If opening the display fails, nullptr is returned.

Parameters

display_name The name of the display to open.

Returns: A Gdk::Display.

◆ operator=()

Display & Gdk::Display::operator= ( Display && src )

noexcept

◆ prepare_gl()

void Gdk::Display::prepare_gl ( )

Checks that OpenGL is available for this display and ensures that it is properly initialized.

When this fails, an exception will be thrown describing the error.

Note that even if this function succeeds, creating a Gdk::GLContext may still fail.

This function is idempotent. Calling it multiple times will just return the same value or error.

You never need to call this function, GDK will call it automatically as needed. But you can use it as a check when setting up code that might make use of OpenGL.

Since gtkmm 4.4:

Exceptions

Glib::Error

◆ property_composited()

Glib::PropertyProxy_ReadOnly< bool > Gdk::Display::property_composited ( ) const

true if the display properly composites the alpha channel.

Default value: true

Returns: A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

◆ property_dmabuf_formats()

Glib::PropertyProxy_ReadOnly< Glib::RefPtr< DmabufFormats > > Gdk::Display::property_dmabuf_formats ( ) const

The dma-buf formats that are supported on this display.

Since gtkmm 4.14:

Returns: A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

◆ property_input_shapes()

Glib::PropertyProxy_ReadOnly< bool > Gdk::Display::property_input_shapes ( ) const

true if the display supports input shapes.

Default value: true

Returns: A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

◆ property_rgba()

Glib::PropertyProxy_ReadOnly< bool > Gdk::Display::property_rgba ( ) const

true if the display supports an alpha channel.

Default value: true

Returns: A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

◆ property_shadow_width()

Glib::PropertyProxy_ReadOnly< bool > Gdk::Display::property_shadow_width ( ) const

true if the display supports extensible frames.

Since gtkmm 4.14:

Default value: true

Returns: A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

◆ put_event()

void Gdk::Display::put_event ( const Glib::RefPtr< const Event > & event )

Adds the given event to the event queue for display.

Deprecated: 4.10: This function is only useful in very special situations and should not be used by applications.

Deprecated:: This function is only useful in very special situations and should not be used by applications.

Parameters

event A Gdk::Event.

◆ signal_closed()

Glib::SignalProxy< void(bool)> Gdk::Display::signal_closed ( )

Slot Prototype:: void on_my_closed(bool is_error)

Flags: Run Last

Emitted when the connection to the windowing system for display is closed.

Parameters

is_error true if the display was closed due to an error.

◆ signal_opened()

Glib::SignalProxy< void()> Gdk::Display::signal_opened ( )

Slot Prototype:: void on_my_opened()

Flags: Run Last

Emitted when the connection to the windowing system for display is opened.

◆ signal_seat_added()

Glib::SignalProxy< void(const Glib::RefPtr< Seat > &)> Gdk::Display::signal_seat_added ( )

Slot Prototype:: void on_my_seat_added(const Glib::RefPtr<Seat>& seat)

Flags: Run Last

Emitted whenever a new seat is made known to the windowing system.

Parameters

seat	The seat that was just added.

◆ signal_seat_removed()

Glib::SignalProxy< void(const Glib::RefPtr< Seat > &)> Gdk::Display::signal_seat_removed ( )

Slot Prototype:: void on_my_seat_removed(const Glib::RefPtr<Seat>& seat)

Flags: Run Last

Emitted whenever a seat is removed by the windowing system.

Parameters

seat	The seat that was just removed.

◆ signal_setting_changed()

Glib::SignalProxy< void(const Glib::ustring &)> Gdk::Display::signal_setting_changed ( )

Slot Prototype:: void on_my_setting_changed(const Glib::ustring& setting)

Flags: Run Last

Emitted whenever a setting changes its value.

Parameters

setting The name of the setting that changed.

◆ supports_input_shapes()

bool Gdk::Display::supports_input_shapes ( ) const

Returns true if the display supports input shapes.

This means that Gdk::Surface::set_input_region() can be used to modify the input shape of surfaces on display.

On modern displays, this value is always true.

Returns: true if surfaces with modified input shape are supported.

◆ supports_shadow_width()

bool Gdk::Display::supports_shadow_width ( ) const

Returns whether it's possible for a surface to draw outside of the window area.

If true is returned the application decides if it wants to draw shadows. If false is returned, the compositor decides if it wants to draw shadows.

Since gtkmm 4.14:

Returns: true if surfaces can draw shadows or false if the display does not support this functionality.

◆ sync()

void Gdk::Display::sync ( )

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 sync() before GdkX11::Display::error_trap_pop() 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.

Friends And Related Symbol Documentation

◆ wrap()

Glib::RefPtr< Gdk::Display > wrap	(	GdkDisplay *	object,
		bool	take_copy = `false`
	)

A Glib::wrap() method for this object.

Parameters

object	The C instance.
take_copy	False if the result should take ownership of the C instance. True if it should take a new copy or ref.

Returns: A C++ instance that wraps this C instance.

Public Member Functions

Static Public Member Functions

Protected Member Functions

Related Symbols

Detailed Description

Constructor & Destructor Documentation

◆ Display() [1/2]

◆ ~Display()

◆ Display() [2/2]

Member Function Documentation

◆ beep()

◆ close()

◆ create_gl_context()

◆ device_is_grabbed()

◆ flush()

◆ get_app_launch_context() [1/2]

◆ get_app_launch_context() [2/2]

◆ get_clipboard() [1/2]

◆ get_clipboard() [2/2]

◆ get_default()

◆ get_default_seat() [1/2]

◆ get_default_seat() [2/2]

◆ get_dmabuf_formats() [1/2]

◆ get_dmabuf_formats() [2/2]

◆ get_monitor_at_surface() [1/2]

◆ get_monitor_at_surface() [2/2]

◆ get_monitors() [1/2]

◆ get_monitors() [2/2]

◆ get_name()

◆ get_primary_clipboard() [1/2]

◆ get_primary_clipboard() [2/2]

◆ get_setting()

◆ get_startup_notification_id()

◆ get_type()

◆ gobj() [1/2]

◆ gobj() [2/2]

◆ gobj_copy()

◆ is_closed()

◆ is_composited()

◆ is_rgba()

◆ list_seats() [1/2]

◆ list_seats() [2/2]

◆ notify_startup_complete()

◆ open()

◆ operator=()

◆ prepare_gl()

◆ property_composited()

◆ property_dmabuf_formats()

◆ property_input_shapes()

◆ property_rgba()

◆ property_shadow_width()

◆ put_event()

◆ signal_closed()

◆ signal_opened()

◆ signal_seat_added()

◆ signal_seat_removed()

◆ signal_setting_changed()

◆ supports_input_shapes()

◆ supports_shadow_width()

◆ sync()

Friends And Related Symbol Documentation

◆ wrap()