CdkDisplayManager: CDK 3 Reference Manual

CdkDisplayManager

CdkDisplayManager — Maintains a list of all open CdkDisplays

Functions

CdkDisplayManager *	cdk_display_manager_get ()
CdkDisplay *	cdk_display_manager_get_default_display ()
void	cdk_display_manager_set_default_display ()
GSList *	cdk_display_manager_list_displays ()
CdkDisplay *	cdk_display_manager_open_display ()

Properties

CdkDisplay *

default-display

Read / Write

Signals

void

display-opened

Run Last

Types and Values

CdkDisplayManager

Object Hierarchy

    GObject
    ╰── CdkDisplayManager

Includes

#include <cdk/cdk.h>

Description

The purpose of the CdkDisplayManager singleton object is to offer notification when displays appear or disappear or the default display changes.

You can use cdk_display_manager_get() to obtain the CdkDisplayManager singleton, but that should be rarely necessary. Typically, initializing CTK+ opens a display that you can work with without ever accessing the CdkDisplayManager.

The CDK library can be built with support for multiple backends. The CdkDisplayManager object determines which backend is used at runtime.

When writing backend-specific code that is supposed to work with multiple CDK backends, you have to consider both compile time and runtime. At compile time, use the CDK_WINDOWING_X11, CDK_WINDOWING_WIN32 macros, etc. to find out which backends are present in the CDK library you are building your application against. At runtime, use type-check macros like CDK_IS_X11_DISPLAY() to find out which backend is in use:

Backend-specific code

#ifdef CDK_WINDOWING_X11
  if (CDK_IS_X11_DISPLAY (display))
    {
      // make X11-specific calls here
    }
  else
#endif
#ifdef CDK_WINDOWING_QUARTZ
  if (CDK_IS_QUARTZ_DISPLAY (display))
    {
      // make Quartz-specific calls here
    }
  else
#endif
  g_error ("Unsupported CDK backend");

Functions

cdk_display_manager_get ()

CdkDisplayManager *
cdk_display_manager_get (void);

Gets the singleton CdkDisplayManager object.

When called for the first time, this function consults the CDK_BACKEND environment variable to find out which of the supported CDK backends to use (in case CDK has been compiled with multiple backends). Applications can use cdk_set_allowed_backends() to limit what backends can be used.

Returns

The global CdkDisplayManager singleton; cdk_parse_args(), cdk_init(), or cdk_init_check() must have been called first.

[transfer none]

Since: 2.2

cdk_display_manager_get_default_display ()

CdkDisplay *
cdk_display_manager_get_default_display
                               (CdkDisplayManager *manager);

Gets the default CdkDisplay.

Parameters

manager

a CdkDisplayManager

Returns

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

[nullable][transfer none]

Since: 2.2

cdk_display_manager_set_default_display ()

void
cdk_display_manager_set_default_display
                               (CdkDisplayManager *manager,
                                CdkDisplay *display);

Sets display as the default display.

Parameters

manager	a CdkDisplayManager
display	a CdkDisplay

Since: 2.2

cdk_display_manager_list_displays ()

GSList *
cdk_display_manager_list_displays (CdkDisplayManager *manager);

List all currently open displays.

Parameters

manager

a CdkDisplayManager

Returns

a newly allocated GSList of CdkDisplay objects. Free with g_slist_free() when you are done with it.

[transfer container][element-type CdkDisplay]

Since: 2.2

cdk_display_manager_open_display ()

CdkDisplay *
cdk_display_manager_open_display (CdkDisplayManager *manager,
                                  const gchar *name);

Opens a display.

Parameters

manager	a CdkDisplayManager
name	the name of the display to open

Returns

a CdkDisplay, or NULL if the display could not be opened.

[nullable][transfer none]

Since: 3.0

Types and Values