GdkScreen

GdkScreen

Functions

GdkScreen * gdk_screen_get_default ()
GdkColormap * gdk_screen_get_default_colormap ()
void gdk_screen_set_default_colormap ()
GdkColormap * gdk_screen_get_system_colormap ()
GdkVisual * gdk_screen_get_system_visual ()
GdkColormap * gdk_screen_get_rgb_colormap ()
GdkVisual * gdk_screen_get_rgb_visual ()
GdkColormap * gdk_screen_get_rgba_colormap ()
GdkVisual * gdk_screen_get_rgba_visual ()
gboolean gdk_screen_is_composited ()
GdkWindow * gdk_screen_get_root_window ()
GdkDisplay * gdk_screen_get_display ()
gint gdk_screen_get_number ()
gint gdk_screen_get_width ()
gint gdk_screen_get_height ()
gint gdk_screen_get_width_mm ()
gint gdk_screen_get_height_mm ()
GList * gdk_screen_list_visuals ()
GList * gdk_screen_get_toplevel_windows ()
gchar * gdk_screen_make_display_name ()
gint gdk_screen_get_n_monitors ()
gint gdk_screen_get_primary_monitor ()
void gdk_screen_get_monitor_geometry ()
gint gdk_screen_get_monitor_at_point ()
gint gdk_screen_get_monitor_at_window ()
gint gdk_screen_get_monitor_height_mm ()
gint gdk_screen_get_monitor_width_mm ()
gchar * gdk_screen_get_monitor_plug_name ()
void gdk_screen_broadcast_client_message ()
gboolean gdk_screen_get_setting ()
const cairo_font_options_t * gdk_screen_get_font_options ()
void gdk_screen_set_font_options ()
gdouble gdk_screen_get_resolution ()
void gdk_screen_set_resolution ()
GdkWindow * gdk_screen_get_active_window ()
GList * gdk_screen_get_window_stack ()
gboolean gdk_spawn_on_screen ()
gboolean gdk_spawn_on_screen_with_pipes ()
gboolean gdk_spawn_command_line_on_screen ()

Properties

gpointer font-options Read / Write
double resolution Read / Write

Signals

void composited-changed Run Last
void monitors-changed Run Last
void size-changed Run Last

Types and Values

Object Hierarchy

    GObject
    ╰── GdkScreen

Includes

#include <gdk/gdk.h>

Description

Functions

gdk_screen_get_default ()

GdkScreen *
gdk_screen_get_default (void);

Gets the default screen for the default display. (See gdk_display_get_default()).

Returns

a GdkScreen, or NULL if there is no default display.

[transfer none]

Since: 2.2


gdk_screen_get_default_colormap ()

GdkColormap *
gdk_screen_get_default_colormap (GdkScreen *screen);

Gets the default colormap for screen .

Parameters

screen

a GdkScreen

 

Returns

the default GdkColormap.

[transfer none]

Since: 2.2


gdk_screen_set_default_colormap ()

void
gdk_screen_set_default_colormap (GdkScreen *screen,
                                 GdkColormap *colormap);

Sets the default colormap for screen .

Parameters

screen

a GdkScreen

 

colormap

a GdkColormap

 

Since: 2.2


gdk_screen_get_system_colormap ()

GdkColormap *
gdk_screen_get_system_colormap (GdkScreen *screen);

Gets the system's default colormap for screen

Parameters

screen

a GdkScreen

 

Returns

the default colormap for screen .

[transfer none]

Since: 2.2


gdk_screen_get_system_visual ()

GdkVisual *
gdk_screen_get_system_visual (GdkScreen *screen);

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.

Parameters

screen

a GdkScreen.

 

Returns

the system visual.

[transfer none]

Since: 2.2


gdk_screen_get_rgb_colormap ()

GdkColormap *
gdk_screen_get_rgb_colormap (GdkScreen *screen);

gdk_screen_get_rgb_colormap has been deprecated since version 2.22 and should not be used in newly-written code.

Use gdk_screen_get_system_colormap()

Gets the preferred colormap for rendering image data on screen . Not a very useful function; historically, GDK could only render RGB image data to one colormap and visual, but in the current version it can render to any colormap and visual. So there's no need to call this function.

Parameters

screen

a GdkScreen.

 

Returns

the preferred colormap.

[transfer none]

Since: 2.2


gdk_screen_get_rgb_visual ()

GdkVisual *
gdk_screen_get_rgb_visual (GdkScreen *screen);

gdk_screen_get_rgb_visual has been deprecated since version 2.22 and should not be used in newly-written code.

Use gdk_screen_get_system_visual()

Gets a "preferred visual" chosen by GdkRGB for rendering image data on screen . In previous versions of GDK, this was the only visual GdkRGB could use for rendering. In current versions, it's simply the visual GdkRGB would have chosen as the optimal one in those previous versions. GdkRGB can now render to drawables with any visual.

Parameters

screen

a GdkScreen

 

Returns

The GdkVisual chosen by GdkRGB.

[transfer none]

Since: 2.2


gdk_screen_get_rgba_colormap ()

GdkColormap *
gdk_screen_get_rgba_colormap (GdkScreen *screen);

Gets a colormap to use for creating windows or pixmaps with an alpha channel. The windowing system on which GTK+ is running may not support this capability, in which case NULL will be returned. Even if a non-NULL 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().

Parameters

screen

a GdkScreen.

 

Returns

a colormap to use for windows with an alpha channel or NULL if the capability is not available.

[transfer none]

Since: 2.8


gdk_screen_get_rgba_visual ()

GdkVisual *
gdk_screen_get_rgba_visual (GdkScreen *screen);

Gets a visual to use for creating windows or pixmaps with an alpha channel. See the docs for gdk_screen_get_rgba_colormap() for caveats.

Parameters

screen

a GdkScreen

 

Returns

a visual to use for windows with an alpha channel or NULL if the capability is not available.

[transfer none]

Since: 2.8


gdk_screen_is_composited ()

gboolean
gdk_screen_is_composited (GdkScreen *screen);

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 .

Parameters

screen

a GdkScreen

 

Returns

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

Since: 2.10


gdk_screen_get_root_window ()

GdkWindow *
gdk_screen_get_root_window (GdkScreen *screen);

Gets the root window of screen .

Parameters

screen

a GdkScreen

 

Returns

the root window.

[transfer none]

Since: 2.2


gdk_screen_get_display ()

GdkDisplay *
gdk_screen_get_display (GdkScreen *screen);

Gets the display to which the screen belongs.

Parameters

screen

a GdkScreen

 

Returns

the display to which screen belongs

Since: 2.2


gdk_screen_get_number ()

gint
gdk_screen_get_number (GdkScreen *screen);

Gets the index of screen among the screens in the display to which it belongs. (See gdk_screen_get_display())

Parameters

screen

a GdkScreen

 

Returns

the index

Since: 2.2


gdk_screen_get_width ()

gint
gdk_screen_get_width (GdkScreen *screen);

Gets the width of screen in pixels

Parameters

screen

a GdkScreen

 

Returns

the width of screen in pixels.

Since: 2.2


gdk_screen_get_height ()

gint
gdk_screen_get_height (GdkScreen *screen);

Gets the height of screen in pixels

Parameters

screen

a GdkScreen

 

Returns

the height of screen in pixels.

Since: 2.2


gdk_screen_get_width_mm ()

gint
gdk_screen_get_width_mm (GdkScreen *screen);

Gets the width of screen in millimeters. Note that on some X servers this value will not be correct.

Parameters

screen

a GdkScreen

 

Returns

the width of screen in millimeters.

Since: 2.2


gdk_screen_get_height_mm ()

gint
gdk_screen_get_height_mm (GdkScreen *screen);

Returns the height of screen in millimeters. Note that on some X servers this value will not be correct.

Parameters

screen

a GdkScreen

 

Returns

the heigth of screen in millimeters.

Since: 2.2


gdk_screen_list_visuals ()

GList *
gdk_screen_list_visuals (GdkScreen *screen);

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.

Call g_list_free() on the return value when you're finished with it.

Parameters

screen

the relevant GdkScreen.

 

Returns

a list of visuals; the list must be freed, but not its contents.

[transfer container][element-type GdkVisual]

Since: 2.2


gdk_screen_get_toplevel_windows ()

GList *
gdk_screen_get_toplevel_windows (GdkScreen *screen);

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()).

The returned list should be freed with g_list_free(), but its elements need not be freed.

Parameters

screen

The GdkScreen where the toplevels are located.

 

Returns

list of toplevel windows, free with g_list_free().

[transfer container][element-type GdkWindow]

Since: 2.2


gdk_screen_make_display_name ()

gchar *
gdk_screen_make_display_name (GdkScreen *screen);

Determines the name to pass to gdk_display_open() to get a GdkDisplay with this screen as the default screen.

Parameters

screen

a GdkScreen

 

Returns

a newly allocated string, free with g_free()

Since: 2.2


gdk_screen_get_n_monitors ()

gint
gdk_screen_get_n_monitors (GdkScreen *screen);

Returns the number of monitors which screen consists of.

Parameters

screen

a GdkScreen

 

Returns

number of monitors which screen consists of

Since: 2.2


gdk_screen_get_primary_monitor ()

gint
gdk_screen_get_primary_monitor (GdkScreen *screen);

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.

Parameters

screen

a GdkScreen.

 

Returns

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

Since: 2.20


gdk_screen_get_monitor_geometry ()

void
gdk_screen_get_monitor_geometry (GdkScreen *screen,
                                 gint monitor_num,
                                 GdkRectangle *dest);

Retrieves the GdkRectangle representing the size and position of the individual monitor within the entire screen area.

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

Parameters

screen

a GdkScreen

 

monitor_num

the monitor number, between 0 and gdk_screen_get_n_monitors (screen)

 

dest

a GdkRectangle to be filled with the monitor geometry

 

Since: 2.2


gdk_screen_get_monitor_at_point ()

gint
gdk_screen_get_monitor_at_point (GdkScreen *screen,
                                 gint x,
                                 gint y);

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

Parameters

screen

a GdkScreen.

 

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.

Since: 2.2


gdk_screen_get_monitor_at_window ()

gint
gdk_screen_get_monitor_at_window (GdkScreen *screen,
                                  GdkWindow *window);

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

Parameters

screen

a GdkScreen.

 

window

a GdkWindow

 

returns

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

 

Since: 2.2


gdk_screen_get_monitor_height_mm ()

gint
gdk_screen_get_monitor_height_mm (GdkScreen *screen,
                                  gint monitor_num);

Gets the height in millimeters of the specified monitor.

Parameters

screen

a GdkScreen

 

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

Since: 2.14


gdk_screen_get_monitor_width_mm ()

gint
gdk_screen_get_monitor_width_mm (GdkScreen *screen,
                                 gint monitor_num);

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

Parameters

screen

a GdkScreen

 

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

Since: 2.14


gdk_screen_get_monitor_plug_name ()

gchar *
gdk_screen_get_monitor_plug_name (GdkScreen *screen,
                                  gint monitor_num);

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

Parameters

screen

a GdkScreen

 

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 NULL if the name cannot be determined

Since: 2.14


gdk_screen_broadcast_client_message ()

void
gdk_screen_broadcast_client_message (GdkScreen *screen,
                                     GdkEvent *event);

On X11, sends an X ClientMessage event to all toplevel windows on screen .

Toplevel windows are determined by checking for the WM_STATE property, as described in the Inter-Client Communication Conventions Manual (ICCCM). If no windows are found with the WM_STATE property set, the message is sent to all children of the root window.

On Windows, broadcasts a message registered with the name GDK_WIN32_CLIENT_MESSAGE to all top-level windows. The amount of data is limited to one long, i.e. four bytes.

Parameters

screen

the GdkScreen where the event will be broadcasted.

 

event

the GdkEvent.

 

Since: 2.2


gdk_screen_get_setting ()

gboolean
gdk_screen_get_setting (GdkScreen *screen,
                        const gchar *name,
                        GValue *value);

Retrieves a desktop-wide setting such as double-click time for the GdkScreen screen .

FIXME needs a list of valid settings here, or a link to more information.

Parameters

screen

the GdkScreen where the setting is located

 

name

the name of the setting

 

value

location to store the value of the setting

 

Returns

TRUE if the setting existed and a value was stored in value , FALSE otherwise.

Since: 2.2


gdk_screen_get_font_options ()

const cairo_font_options_t *
gdk_screen_get_font_options (GdkScreen *screen);

Gets any options previously set with gdk_screen_set_font_options().

Parameters

screen

a GdkScreen

 

Returns

the current font options, or NULL if no default font options have been set.

Since: 2.10


gdk_screen_set_font_options ()

void
gdk_screen_set_font_options (GdkScreen *screen,
                             const cairo_font_options_t *options);

Sets the default font options for the screen. These options will be set on any PangoContext'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.

Parameters

screen

a GdkScreen

 

options

a cairo_font_options_t, or NULL to unset any previously set default font options.

[allow-none]

Since: 2.10


gdk_screen_get_resolution ()

gdouble
gdk_screen_get_resolution (GdkScreen *screen);

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

Parameters

screen

a GdkScreen

 

Returns

the current resolution, or -1 if no resolution has been set.

Since: 2.10


gdk_screen_set_resolution ()

void
gdk_screen_set_resolution (GdkScreen *screen,
                           gdouble dpi);

Sets the resolution for font handling on the screen. This is a scale factor between points specified in a PangoFontDescription and cairo units. The default value is 96, meaning that a 10 point font will be 13 units high. (10 * 96. / 72. = 13.3).

Parameters

screen

a GdkScreen

 

dpi

the resolution in "dots per inch". (Physical inches aren't actually involved; the terminology is conventional.)

 

Since: 2.10


gdk_screen_get_active_window ()

GdkWindow *
gdk_screen_get_active_window (GdkScreen *screen);

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 NULL.

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

The returned window should be unrefed using g_object_unref() when no longer needed.

Parameters

screen

a GdkScreen

 

Returns

the currently active window, or NULL.

Since: 2.10


gdk_screen_get_window_stack ()

GList *
gdk_screen_get_window_stack (GdkScreen *screen);

Returns a GList of GdkWindows 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 NULL.

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

The returned list is newly allocated and owns references to the windows it contains, so it should be freed using g_list_free() and its windows unrefed using g_object_unref() when no longer needed.

Parameters

screen

a GdkScreen

 

Returns

a list of GdkWindows for the current window stack, or NULL.

[transfer full][element-type GdkWindow]

Since: 2.10


gdk_spawn_on_screen ()

gboolean
gdk_spawn_on_screen (GdkScreen *screen,
                     const gchar *working_directory,
                     gchar **argv,
                     gchar **envp,
                     GSpawnFlags flags,
                     GSpawnChildSetupFunc child_setup,
                     gpointer user_data,
                     gint *child_pid,
                     GError **error);

gdk_spawn_on_screen has been deprecated since version 2.24 and should not be used in newly-written code.

This function is being removed in 3.0. Use either g_spawn_sync(), g_spawn_async(), or GdkAppLaunchContext instead.

Like g_spawn_async(), except the child process is spawned in such an environment that on calling gdk_display_open() it would be returned a GdkDisplay with screen as the default screen.

This is useful for applications which wish to launch an application on a specific screen.

Parameters

screen

a GdkScreen

 

working_directory

child's current working directory, or NULL to inherit parent's

 

argv

child's argument vector

 

envp

child's environment, or NULL to inherit parent's

 

flags

flags from GSpawnFlags

 

child_setup

function to run in the child just before exec()

 

user_data

user data for child_setup

 

child_pid

return location for child process ID, or NULL

 

error

return location for error

 

Returns

TRUE on success, FALSE if error is set

Since: 2.4


gdk_spawn_on_screen_with_pipes ()

gboolean
gdk_spawn_on_screen_with_pipes (GdkScreen *screen,
                                const gchar *working_directory,
                                gchar **argv,
                                gchar **envp,
                                GSpawnFlags flags,
                                GSpawnChildSetupFunc child_setup,
                                gpointer user_data,
                                gint *child_pid,
                                gint *standard_input,
                                gint *standard_output,
                                gint *standard_error,
                                GError **error);

gdk_spawn_on_screen_with_pipes has been deprecated since version 2.24 and should not be used in newly-written code.

This function is being removed in 3.0. Use either g_spawn_async_with_pipes() or GdkAppLaunchContext instead.

Like g_spawn_async_with_pipes(), except the child process is spawned in such an environment that on calling gdk_display_open() it would be returned a GdkDisplay with screen as the default screen.

This is useful for applications which wish to launch an application on a specific screen.

Parameters

screen

a GdkScreen

 

working_directory

child's current working directory, or NULL to inherit parent's

 

argv

child's argument vector

 

envp

child's environment, or NULL to inherit parent's

 

flags

flags from GSpawnFlags

 

child_setup

function to run in the child just before exec()

 

user_data

user data for child_setup

 

child_pid

return location for child process ID, or NULL

 

standard_input

return location for file descriptor to write to child's stdin, or NULL

 

standard_output

return location for file descriptor to read child's stdout, or NULL

 

standard_error

return location for file descriptor to read child's stderr, or NULL

 

error

return location for error

 

Returns

TRUE on success, FALSE if an error was set

Since: 2.4


gdk_spawn_command_line_on_screen ()

gboolean
gdk_spawn_command_line_on_screen (GdkScreen *screen,
                                  const gchar *command_line,
                                  GError **error);

gdk_spawn_command_line_on_screen has been deprecated since version 2.24 and should not be used in newly-written code.

This function is being removed in 3.0. Use either g_spawn_command_line_sync(), g_spawn_command_line_async() or GdkAppLaunchContext instead.

Like g_spawn_command_line_async(), except the child process is spawned in such an environment that on calling gdk_display_open() it would be returned a GdkDisplay with screen as the default screen.

This is useful for applications which wish to launch an application on a specific screen.

Parameters

screen

a GdkScreen

 

command_line

a command line

 

error

return location for errors

 

Returns

TRUE on success, FALSE if error is set.

Since: 2.4

Types and Values

GdkScreen

typedef struct _GdkScreen GdkScreen;

Property Details

The “font-options” property

  “font-options”             gpointer

The default font options for the screen.

Owner: GdkScreen

Flags: Read / Write


The “resolution” property

  “resolution”               double

The resolution for fonts on the screen.

Owner: GdkScreen

Flags: Read / Write

Default value: -1

Signal Details

The “composited-changed” signal

void
user_function (GdkScreen *screen,
               gpointer   user_data)

The ::composited-changed signal is emitted when the composited status of the screen changes

Parameters

screen

the object on which the signal is emitted

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last

Since: 2.10


The “monitors-changed” signal

void
user_function (GdkScreen *screen,
               gpointer   user_data)

The ::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.

Parameters

screen

the object on which the signal is emitted

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last

Since: 2.14


The “size-changed” signal

void
user_function (GdkScreen *screen,
               gpointer   user_data)

The ::size-changed signal is emitted when the pixel width or height of a screen changes.

Parameters

screen

the object on which the signal is emitted

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last

Since: 2.2