C++ GDK_SCREEN_GET_CLASS函数代码示例

/**
 * gdk_screen_get_window_stack:
 * @screen: a #GdkScreen
 *
 * 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](http://www.freedesktop.org/Standards/wm-spec).
 * 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.
 *
 * Returns: (nullable) (transfer full) (element-type GdkWindow): a
 *     list of #GdkWindows for the current window stack, or %NULL.
 *
 * Since: 2.10
 **/
GList *
gdk_screen_get_window_stack (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);

  return GDK_SCREEN_GET_CLASS (screen)->get_window_stack (screen);
}

/**
 * gdk_screen_get_root_window:
 * @screen: a #GdkScreen
 *
 * Gets the root window of @screen.
 *
 * Returns: (transfer none): the root window
 *
 * Since: 2.2
 **/
GdkWindow *
gdk_screen_get_root_window (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);

  return GDK_SCREEN_GET_CLASS (screen)->get_root_window (screen);
}

/**
 * gdk_screen_get_primary_monitor:
 * @screen: a #GdkScreen.
 *
 * 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.
 *
 * Returns: An integer index for the primary monitor, or 0 if none is configured.
 *
 * Since: 2.20
 */
gint
gdk_screen_get_primary_monitor (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);

  return GDK_SCREEN_GET_CLASS (screen)->get_primary_monitor (screen);
}

/**
 * gdk_screen_get_setting:
 * @screen: the #GdkScreen where the setting is located
 * @name: the name of the setting
 * @value: location to store the value of the setting
 *
 * 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.
 *
 * Returns: %TRUE if the setting existed and a value was stored
 *   in @value, %FALSE otherwise.
 *
 * Since: 2.2
 **/
gboolean
gdk_screen_get_setting (GdkScreen   *screen,
			const gchar *name,
			GValue      *value)
{
  return GDK_SCREEN_GET_CLASS(screen)->get_setting (screen, name, value);
}

/**
 * gdk_screen_get_rgba_visual:
 * @screen: a #GdkScreen
 *
 * 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 %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().
 *
 * Returns: (nullable) (transfer none): a visual to use for windows
 *     with an alpha channel or %NULL if the capability is not
 *     available.
 *
 * Since: 2.8
 **/
GdkVisual *
gdk_screen_get_rgba_visual (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);

  return GDK_SCREEN_GET_CLASS (screen)->get_rgba_visual (screen);
}

/**
 * gdk_screen_list_visuals:
 * @screen: the relevant #GdkScreen.
 *
 * 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.
 *
 * Returns: (transfer container) (element-type GdkVisual):
 *     a list of visuals; the list must be freed, but not its contents
 *
 * Since: 2.2
 **/
GList *
gdk_screen_list_visuals (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);

  return GDK_SCREEN_GET_CLASS (screen)->list_visuals (screen);
}

/**
 * gdk_screen_make_display_name:
 * @screen: a #GdkScreen
 *
 * Determines the name to pass to gdk_display_open() to get
 * a #GdkDisplay with this screen as the default screen.
 *
 * Returns: a newly allocated string, free with g_free()
 *
 * Since: 2.2
 **/
gchar *
gdk_screen_make_display_name (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);

  return GDK_SCREEN_GET_CLASS (screen)->make_display_name (screen);
}

/**
 * gdk_screen_is_composited:
 * @screen: a #GdkScreen
 *
 * 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.
 *
 * Returns: Whether windows with RGBA visuals can reasonably be
 * expected to have their alpha channels drawn correctly on the screen.
 *
 * Since: 2.10
 **/
gboolean
gdk_screen_is_composited (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), FALSE);

  return GDK_SCREEN_GET_CLASS (screen)->is_composited (screen);
}

/**
 * gdk_visual_get_best:
 *
 * Get the visual with the most available colors for the default
 * GDK screen. The return value should not be freed.
 *
 * Returns: (transfer none): best visual
 */
GdkVisual*
gdk_visual_get_best (void)
{
  GdkScreen *screen = gdk_screen_get_default();

  return GDK_SCREEN_GET_CLASS(screen)->visual_get_best (screen);
}

/**
 * gdk_screen_get_monitor_workarea:
 * @screen: a #GdkScreen
 * @monitor_num: the monitor number
 * @dest: (out) (allow-none): a #GdkRectangle to be filled with
 *     the monitor workarea
 *
 * Retrieves the #GdkRectangle 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 gdk_screen_get_n_monitors().
 *
 * Since: 3.4
 */
void
gdk_screen_get_monitor_workarea (GdkScreen    *screen,
                                 gint          monitor_num,
                                 GdkRectangle *dest)
{
  GDK_SCREEN_GET_CLASS(screen)->get_monitor_workarea (screen, monitor_num, dest);
}

/**
 * gdk_visual_get_best_with_depth:
 * @depth: a bit depth
 *
 * Get the best visual with depth @depth for the default GDK screen.
 * Color visuals and visuals with mutable colormaps are preferred
 * over grayscale or fixed-colormap visuals. The return value should
 * not be freed. %NULL may be returned if no visual supports @depth.
 *
 * Returns: (transfer none): best visual for the given depth
 */
GdkVisual*
gdk_visual_get_best_with_depth (gint depth)
{
  GdkScreen *screen = gdk_screen_get_default();

  return GDK_SCREEN_GET_CLASS(screen)->visual_get_best_with_depth (screen, depth);
}

/**
 * gdk_screen_get_display:
 * @screen: a #GdkScreen
 *
 * Gets the display to which the @screen belongs.
 *
 * Returns: (transfer none): the display to which @screen belongs
 *
 * Since: 2.2
 **/
GdkDisplay *
gdk_screen_get_display (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);

  return GDK_SCREEN_GET_CLASS (screen)->get_display (screen);
}

/**
 * gdk_screen_get_height_mm:
 * @screen: a #GdkScreen
 *
 * 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.
 *
 * Returns: the heigth of @screen in millimeters.
 *
 * Since: 2.2
 **/
gint
gdk_screen_get_height_mm (GdkScreen *screen)
{
  g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);

  return GDK_SCREEN_GET_CLASS (screen)->get_height_mm (screen);
}

/**
 * gdk_query_visual_types:
 * @visual_types: (out) (array length=count) (transfer none): return
 *     location for the available visual types
 * @count: return location for the number of available visual types
 *
 * This function returns the available visual types for the default
 * screen. It’s equivalent to listing the visuals
 * (gdk_list_visuals()) and then looking at the type field in each
 * visual, removing duplicates.
 *
 * The array returned by this function should not be freed.
 */
void
gdk_query_visual_types (GdkVisualType **visual_types,
                        gint           *count)
{
  GdkScreen *screen = gdk_screen_get_default();

  GDK_SCREEN_GET_CLASS(screen)->query_visual_types (screen, visual_types, count);
}

/**
 * gdk_visual_get_best_with_type:
 * @visual_type: a visual type
 *
 * Get the best visual of the given @visual_type for the default GDK screen.
 * Visuals with higher color depths are considered better. The return value
 * should not be freed. %NULL may be returned if no visual has type
 * @visual_type.
 *
 * Returns: (transfer none): best visual of the given type
 */
GdkVisual*
gdk_visual_get_best_with_type (GdkVisualType visual_type)
{
  GdkScreen *screen = gdk_screen_get_default();

  return GDK_SCREEN_GET_CLASS(screen)->visual_get_best_with_type (screen,
                                                                  visual_type);
}