gtkmm: Gdk::Screen Class Reference

Object representing a physical screen Gdk::Screen objects are the GDK representation of a physical screen. More...

#include <gdkmm/screen.h>

Inheritance diagram for Gdk::Screen:

Public Member Functions
	Screen (Screen&& src) noexcept

Screen&	operator= (Screen&& src) noexcept

	~Screen () noexceptoverride

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

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

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

Glib::RefPtr< Visual >	get_system_visual ()
	Get the system’s default visual for screen. More...

Glib::RefPtr< const Visual >	get_system_visual () const
	Get the system’s default visual for screen. More...

Glib::RefPtr< Visual >	get_rgba_visual ()
	Gets a visual to use for creating windows with an alpha channel. More...

Glib::RefPtr< const Visual >	get_rgba_visual () const
	Gets a visual to use for creating windows with an alpha channel. More...

bool	is_composited () const
	Returns whether windows with an RGBA visual can reasonably be expected to have their alpha channel drawn correctly on the screen. More...

Glib::RefPtr< Window >	get_root_window ()
	Gets the root window of screen. More...

Glib::RefPtr< const Window >	get_root_window () const
	Gets the root window of screen. More...

Glib::RefPtr< Display >	get_display ()
	Gets the display to which the screen belongs. More...

Glib::RefPtr< const Display >	get_display () const
	Gets the display to which the screen belongs. More...

int	get_number () const
	Gets the index of screen among the screens in the display to which it belongs. More...

int	get_width () const
	Gets the width of screen in pixels. More...

int	get_height () const
	Gets the height of screen in pixels. More...

int	get_width_mm () const
	Gets the width of screen in millimeters. More...

int	get_height_mm () const
	Returns the height of screen in millimeters. More...

std::vector< Glib::RefPtr< Visual > >	list_visuals ()
	Lists the available visuals for the specified screen. More...

std::vector< Glib::RefPtr< Window > >	get_toplevel_windows ()
	Obtains a list of all toplevel windows known to GDK on the screen screen. More...

Glib::ustring	make_display_name ()
	Determines the name to pass to Gdk::Display::open() to get a Gdk::Display with this screen as the default screen. More...

int	get_n_monitors () const
	Returns the number of monitors which screen consists of. More...

int	get_primary_monitor () const
	Gets the primary monitor for screen. More...

void	get_monitor_geometry (int monitor_num, Rectangle& dest) const
	Retrieves the Gdk::Rectangle representing the size and position of the individual monitor within the entire screen area. More...

Rectangle	get_monitor_workarea (int monitor_num=0) const
	Retrieves the Gdk::Rectangle representing the size and position of the "work area" on a monitor within the entire screen area. More...

int	get_monitor_at_point (int x, int y) const
	Returns the monitor number in which the point ( x, y) is located. More...

int	get_monitor_at_window (const Glib::RefPtr< Window >& window) const
	Returns the number of the monitor in which the largest area of the bounding rectangle of window resides. More...

int	get_monitor_width_mm (int monitor_num) const
	Gets the width in millimeters of the specified monitor, if available. More...

int	get_monitor_height_mm (int monitor_num) const
	Gets the height in millimeters of the specified monitor. More...

Glib::ustring	get_monitor_plug_name (int monitor_num) const
	Returns the output name of the specified monitor. More...

int	get_monitor_scale_factor (int monitor_num)
	Returns the internal scale factor that maps from monitor coordinates to the actual device pixels. More...

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

void	set_font_options (const ::Cairo::FontOptions& options)
	Sets the default font options for the screen. More...

::Cairo::FontOptions	get_font_options () const
	Gets any options previously set with set_font_options(). More...

void	set_resolution (double dpi)
	Sets the resolution for font handling on the screen. More...

double	get_resolution () const
	Gets the resolution for font handling on the screen; see set_resolution() for full details. More...

Glib::RefPtr< Gdk::Window >	get_active_window ()
	Returns the screen’s currently active window. More...

Glib::RefPtr< const Gdk::Window >	get_active_window () const
	Returns the screen’s currently active window. More...

std::vector< Glib::RefPtr< Window > >	get_window_stack ()
	Returns a List of Gdk::Windows representing the current window stack. More...

Glib::SignalProxy< void >	signal_size_changed ()

Glib::SignalProxy< void >	signal_composited_changed ()

Glib::SignalProxy< void >	signal_monitors_changed ()

Glib::PropertyProxy< ::Cairo::FontOptions >	property_font_options ()
	The default font options for the screen. More...

Glib::PropertyProxy_ReadOnly< ::Cairo::FontOptions >	property_font_options () const
	The default font options for the screen. More...

Glib::PropertyProxy< double >	property_resolution ()
	The resolution for fonts on the screen. More...

Glib::PropertyProxy_ReadOnly< double >	property_resolution () const
	The resolution for fonts on the screen. More...

Public Member Functions inherited from Glib::Object
	Object (const Object &)=delete

Object &	operator= (const Object &)=delete

	Object (Object &&src) noexcept

Object &	operator= (Object &&src) noexcept

void *	get_data (const QueryQuark &key)

void	set_data (const Quark &key, void *data)

void	set_data (const Quark &key, void *data, DestroyNotify notify)

void	remove_data (const QueryQuark &quark)

void *	steal_data (const QueryQuark &quark)

Glib::RefPtr< Glib::Object >	wrap (GObject *object, bool take_copy=false)

Public Member Functions inherited from Glib::ObjectBase
	ObjectBase (const ObjectBase &)=delete

ObjectBase &	operator= (const ObjectBase &)=delete

void	set_property_value (const Glib::ustring &property_name, const Glib::ValueBase &value)

void	get_property_value (const Glib::ustring &property_name, Glib::ValueBase &value) const

void	set_property (const Glib::ustring &property_name, const PropertyType &value)

void	get_property (const Glib::ustring &property_name, PropertyType &value) const

void	connect_property_changed (const Glib::ustring &property_name, const sigc::slot< void > &slot)

void	connect_property_changed (const Glib::ustring &property_name, sigc::slot< void > &&slot)

sigc::connection	connect_property_changed_with_return (const Glib::ustring &property_name, const sigc::slot< void > &slot)

sigc::connection	connect_property_changed_with_return (const Glib::ustring &property_name, sigc::slot< void > &&slot)

void	freeze_notify ()

void	thaw_notify ()

virtual void	reference () const

virtual void	unreference () const

GObject *	gobj ()

const GObject *	gobj () const

GObject *	gobj_copy () const

Public Member Functions inherited from sigc::trackable
	trackable () noexcept

	trackable (const trackable &src) noexcept

	trackable (trackable &&src)

	~trackable ()

void	add_destroy_notify_callback (void *data, func_destroy_notify func) const

void	notify_callbacks ()

trackable &	operator= (const trackable &src)

trackable &	operator= (trackable &&src)

void	remove_destroy_notify_callback (void *data) const

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

static Glib::RefPtr< Screen >	get_default ()
	Gets the default screen for the default display. More...

Related Functions
(Note that these are not member functions.)
Glib::RefPtr< Gdk::Screen >	wrap (GdkScreen* object, bool take_copy=false)
	A Glib::wrap() method for this object. More...

Additional Inherited Members
Public Types inherited from Glib::Object
typedef void(*)(gpointer data	DestroyNotify)

Public Types inherited from sigc::trackable
typedef internal::func_destroy_notify	func_destroy_notify

Protected Member Functions inherited from Glib::Object
	Object ()

	Object (const Glib::ConstructParams &construct_params)

	Object (GObject *castitem)

	~Object () noexceptoverride

Protected Member Functions inherited from Glib::ObjectBase
	ObjectBase ()

	ObjectBase (const char *custom_type_name)

	ObjectBase (const std::type_info &custom_type_info)

	ObjectBase (ObjectBase &&src) noexcept

ObjectBase &	operator= (ObjectBase &&src) noexcept

virtual	~ObjectBase () noexcept=0

void	initialize (GObject *castitem)

void	initialize_move (GObject castitem, Glib::ObjectBase previous_wrapper)

Detailed Description

Object representing a physical screen Gdk::Screen objects are the GDK representation of a physical screen.

It is used throughout GDK and GTK+ to specify which screen the top level windows are to be displayed on. It is also used to query the screen specification and default settings such as the screen width (get_width()), etc. Note that a screen may consist of multiple monitors which are merged to form a large screen area.

Constructor & Destructor Documentation

Gdk::Screen::Screen ( Screen&& src )

noexcept

Gdk::Screen::~Screen ( )

overridenoexcept

Member Function Documentation

Glib::RefPtr<Gdk::Window> Gdk::Screen::get_active_window ( )

Returns the screen’s currently active window.

On X11, this is done by inspecting the _NET_ACTIVE_WINDOW property on the root window, as described in the Extended Window Manager Hints. If there is no currently currently active window, or the window manager does not support the _NET_ACTIVE_WINDOW hint, this function returns nullptr.

On other platforms, this function may return nullptr, depending on whether it is implementable on that platform.

The returned window should be unrefed using Glib::object_unref() when no longer needed.

Since gtkmm 2.10:

Returns: The currently active window, or nullptr.

Glib::RefPtr<const Gdk::Window> Gdk::Screen::get_active_window ( ) const

Returns the screen’s currently active window.

On other platforms, this function may return nullptr, depending on whether it is implementable on that platform.

The returned window should be unrefed using Glib::object_unref() when no longer needed.

Since gtkmm 2.10:

Returns: The currently active window, or nullptr.

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

static

Gets the default screen for the default display.

(See Gdk::Display::get_default()).

Since gtkmm 2.2:

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

Glib::RefPtr<Display> Gdk::Screen::get_display ( )

Gets the display to which the screen belongs.

Since gtkmm 2.2:

Returns: The display to which screen belongs.

Glib::RefPtr<const Display> Gdk::Screen::get_display ( ) const

Gets the display to which the screen belongs.

Since gtkmm 2.2:

Returns: The display to which screen belongs.

::Cairo::FontOptions Gdk::Screen::get_font_options ( ) const

Gets any options previously set with set_font_options().

Since gtkmm 2.10:

Returns: The current font options, or nullptr if no default font options have been set.

int Gdk::Screen::get_height ( ) const

Gets the height of screen in pixels.

The returned size is in ”application pixels”, not in ”device pixels” (see get_monitor_scale_factor()).

Since gtkmm 2.2:

Returns: The height of screen in pixels.

int Gdk::Screen::get_height_mm ( ) const

Returns the height of screen in millimeters.

Note that this value is somewhat ill-defined when the screen has multiple monitors of different resolution. It is recommended to use the monitor dimensions instead.

Since gtkmm 2.2:

Returns: The heigth of screen in millimeters.

int Gdk::Screen::get_monitor_at_point	(	int	x,
		int	y
	)		const

Returns the monitor number in which the point ( x, y) is located.

Since gtkmm 2.2:

Parameters

x	The x coordinate in the virtual screen.
y	The y coordinate in the virtual screen.

Returns: The monitor number in which the point ( x, y) lies, or a monitor close to ( x, y) if the point is not in any monitor.

int Gdk::Screen::get_monitor_at_window ( const Glib::RefPtr< Window >& window ) const

Returns the number of the monitor in which the largest area of the bounding rectangle of window resides.

Since gtkmm 2.2:

Parameters

window A Gdk::Window.

Returns: The monitor number in which most of window is located, or if window does not intersect any monitors, a monitor, close to window.

void Gdk::Screen::get_monitor_geometry	(	int	monitor_num,
		Rectangle&	dest
	)		const

Retrieves the Gdk::Rectangle representing the size and position of the individual monitor within the entire screen area.

The returned geometry is in ”application pixels”, not in ”device pixels” (see get_monitor_scale_factor()).

Monitor numbers start at 0. To obtain the number of monitors of screen, use get_n_monitors().

Note that the size of the entire screen area can be retrieved via get_width() and get_height().

Since gtkmm 2.2:

Parameters

monitor_num	The monitor number.
dest	A Gdk::Rectangle to be filled with the monitor geometry.

int Gdk::Screen::get_monitor_height_mm ( int monitor_num ) const

Gets the height in millimeters of the specified monitor.

Since gtkmm 2.14:

Parameters

monitor_num Number of the monitor, between 0 and gdk_screen_get_n_monitors (screen).

Returns: The height of the monitor, or -1 if not available.

Glib::ustring Gdk::Screen::get_monitor_plug_name ( int monitor_num ) const

Returns the output name of the specified monitor.

Usually something like VGA, DVI, or TV, not the actual product name of the display device.

Since gtkmm 2.14:

Parameters

monitor_num Number of the monitor, between 0 and gdk_screen_get_n_monitors (screen).

Returns: A newly-allocated string containing the name of the monitor, or nullptr if the name cannot be determined.

int Gdk::Screen::get_monitor_scale_factor ( int monitor_num )

Returns the internal scale factor that maps from monitor coordinates to the actual device pixels.

On traditional systems this is 1, but on very high density outputs this can be a higher value (often 2).

This can be used if you want to create pixel based data for a particular monitor, but most of the time you’re drawing to a window where it is better to use Gdk::Window::get_scale_factor() instead.

Since gtkmm 3.10:

Parameters

monitor_num Number of the monitor, between 0 and gdk_screen_get_n_monitors (screen).

Returns: The scale factor.

int Gdk::Screen::get_monitor_width_mm ( int monitor_num ) const

Gets the width in millimeters of the specified monitor, if available.

Since gtkmm 2.14:

Parameters

monitor_num Number of the monitor, between 0 and gdk_screen_get_n_monitors (screen).

Returns: The width of the monitor, or -1 if not available.

Rectangle Gdk::Screen::get_monitor_workarea ( int monitor_num = 0 ) const

Retrieves the Gdk::Rectangle representing the size and position of the "work area" on a monitor within the entire screen area.

The work area should be considered when positioning menus and similar popups, to avoid placing them below panels, docks or other desktop components.

Monitor numbers start at 0. To obtain the number of monitors of screen, use get_n_monitors().

Since gtkmm 3.6:

Parameters

monitor_num The monitor number.

Returns: The monitor workarea.

int Gdk::Screen::get_n_monitors ( ) const

Returns the number of monitors which screen consists of.

Since gtkmm 2.2:

Returns: Number of monitors which screen consists of.

int Gdk::Screen::get_number ( ) const

Gets the index of screen among the screens in the display to which it belongs.

(See get_display())

Since gtkmm 2.2:

Returns: The index.

int Gdk::Screen::get_primary_monitor ( ) const

Gets the primary monitor for screen.

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.

If no primary monitor is configured by the user, the return value will be 0, defaulting to the first monitor.

Since gtkmm 2.20:

Returns: An integer index for the primary monitor, or 0 if none is configured.

double Gdk::Screen::get_resolution ( ) const

Gets the resolution for font handling on the screen; see set_resolution() for full details.

Since gtkmm 2.10:

Returns: The current resolution, or -1 if no resolution has been set.

Glib::RefPtr<Visual> Gdk::Screen::get_rgba_visual ( )

Gets a visual to use for creating windows with an alpha channel.

The windowing system on which GTK+ is running may not support this capability, in which case nullptr will be returned. Even if a non-nullptr value is returned, its possible that the window’s alpha channel won’t be honored when displaying the window on the screen: in particular, for X an appropriate windowing manager and compositing manager must be running to provide appropriate display.

This functionality is not implemented in the Windows backend.

For setting an overall opacity for a top-level window, see Gdk::Window::set_opacity().

Since gtkmm 2.8:

Returns: A visual to use for windows with an alpha channel or nullptr if the capability is not available.

Glib::RefPtr<const Visual> Gdk::Screen::get_rgba_visual ( ) const

Gets a visual to use for creating windows with an alpha channel.

This functionality is not implemented in the Windows backend.

For setting an overall opacity for a top-level window, see Gdk::Window::set_opacity().

Since gtkmm 2.8:

Returns: A visual to use for windows with an alpha channel or nullptr if the capability is not available.

Glib::RefPtr<Window> Gdk::Screen::get_root_window ( )

Gets the root window of screen.

Since gtkmm 2.2:

Returns: The root window.

Glib::RefPtr<const Window> Gdk::Screen::get_root_window ( ) const

Gets the root window of screen.

Since gtkmm 2.2:

Returns: The root window.

template <class ValueType >

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

Glib::RefPtr<Visual> Gdk::Screen::get_system_visual ( )

Get the system’s default visual for screen.

This is the visual for the root window of the display. The return value should not be freed.

Since gtkmm 2.2:

Returns: The system visual.

Glib::RefPtr<const Visual> Gdk::Screen::get_system_visual ( ) const

Get the system’s default visual for screen.

This is the visual for the root window of the display. The return value should not be freed.

Since gtkmm 2.2:

Returns: The system visual.

std::vector< Glib::RefPtr<Window> > Gdk::Screen::get_toplevel_windows ( )

Obtains a list of all toplevel windows known to GDK on the screen screen.

A toplevel window is a child of the root window (see gdk_get_default_root_window()).

Since gtkmm 2.2:

Returns: List of toplevel windows.

static GType Gdk::Screen::get_type ( )

static

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

int Gdk::Screen::get_width ( ) const

Gets the width of screen in pixels.

The returned size is in ”application pixels”, not in ”device pixels” (see get_monitor_scale_factor()).

Since gtkmm 2.2:

Returns: The width of screen in pixels.

int Gdk::Screen::get_width_mm ( ) const

Gets the width of screen in millimeters.

Note that this value is somewhat ill-defined when the screen has multiple monitors of different resolution. It is recommended to use the monitor dimensions instead.

Since gtkmm 2.2:

Returns: The width of screen in millimeters.

std::vector< Glib::RefPtr<Window> > Gdk::Screen::get_window_stack ( )

Returns a List of Gdk::Windows representing the current window stack.

On X11, this is done by inspecting the _NET_CLIENT_LIST_STACKING property on the root window, as described in the Extended Window Manager Hints. If the window manager does not support the _NET_CLIENT_LIST_STACKING hint, this function returns nullptr.

On other platforms, this function may return nullptr, depending on whether it is implementable on that platform.

Since gtkmm 2.10:

Returns: A list of Gdk::Windows for the current window stack, or nullptr.

GdkScreen* Gdk::Screen::gobj ( )

inline

Provides access to the underlying C GObject.

const GdkScreen* Gdk::Screen::gobj ( ) const

inline

Provides access to the underlying C GObject.

GdkScreen* Gdk::Screen::gobj_copy ( )

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

bool Gdk::Screen::is_composited ( ) const

Returns whether windows with an RGBA visual can reasonably be expected to have their alpha channel drawn correctly on the screen.

On X11 this function returns whether a compositing manager is compositing screen.

Since gtkmm 2.10:

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

std::vector< Glib::RefPtr<Visual> > Gdk::Screen::list_visuals ( )

Lists the available visuals for the specified screen.

A visual describes a hardware image data format. For example, a visual might support 24-bit color, or 8-bit color, and might expect pixels to be in a certain format.

Since gtkmm 2.2:

Returns: A list of visuals.

Glib::ustring Gdk::Screen::make_display_name ( )

Determines the name to pass to Gdk::Display::open() to get a Gdk::Display with this screen as the default screen.

Since gtkmm 2.2:

Returns: The name.

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

noexcept

Glib::PropertyProxy< ::Cairo::FontOptions > Gdk::Screen::property_font_options ( )

The default font options for the screen.

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

Glib::PropertyProxy_ReadOnly< ::Cairo::FontOptions > Gdk::Screen::property_font_options ( ) const

The default font options for the screen.

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

Glib::PropertyProxy< double > Gdk::Screen::property_resolution ( )

The resolution for fonts on the screen.

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

Glib::PropertyProxy_ReadOnly< double > Gdk::Screen::property_resolution ( ) const

The resolution for fonts on the screen.

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

void Gdk::Screen::set_font_options ( const ::Cairo::FontOptions & options )

Sets the default font options for the screen.

These options will be set on any Pango::Context’s newly created with gdk_pango_context_get_for_screen(). Changing the default set of font options does not affect contexts that have already been created.

Since gtkmm 2.10:

Parameters

options A #cairo_font_options_t, or nullptr to unset any previously set default font options.

void Gdk::Screen::set_resolution ( double dpi )

Sets the resolution for font handling on the screen.

This is a scale factor between points specified in a Pango::FontDescription and cairo units. The default value is 96, meaning that a 10 point font will be 13 units high. (10 * 96. / 72. = 13.3).

Since gtkmm 2.10:

Parameters

dpi	The resolution in “dots per inch”. (Physical inches aren’t actually involved; the terminology is conventional.).

Glib::SignalProxy< void > Gdk::Screen::signal_composited_changed ( )

Slot Prototype:: void on_my_composited_changed()

The signal_composited_changed() signal is emitted when the composited status of the screen changes

Since gtkmm 2.10:

Glib::SignalProxy< void > Gdk::Screen::signal_monitors_changed ( )

Slot Prototype:: void on_my_monitors_changed()

The signal_monitors_changed() signal is emitted when the number, size or position of the monitors attached to the screen change.

Only for X11 and OS X for now. A future implementation for Win32 may be a possibility.

Since gtkmm 2.14:

Glib::SignalProxy< void > Gdk::Screen::signal_size_changed ( )

Slot Prototype:: void on_my_size_changed()

The signal_size_changed() signal is emitted when the pixel width or height of a screen changes.

Since gtkmm 2.2:

Friends And Related Function Documentation

Glib::RefPtr< Gdk::Screen > wrap	(	GdkScreen *	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.

gtkmm: Gdk::Screen Class Reference

Public Member Functions

Static Public Member Functions

Related Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation