Class

GtkIconTheme

Description [src]

class Gtk.IconTheme : GObject.Object
{
  /* No available fields */
}

GtkIconTheme provides a facility for looking up icons by name and size. The main reason for using a name rather than simply providing a filename is to allow different icons to be used depending on what “icon theme” is selected by the user. The operation of icon themes on Linux and Unix follows the Icon Theme Specification There is a fallback icon theme, named hicolor, where applications should install their icons, but additional icon themes can be installed as operating system vendors and users choose.

Named icons are similar to the deprecated [Stock Items][gtkstock], and the distinction between the two may be a bit confusing. A few things to keep in mind:

  • Stock images usually are used in conjunction with [Stock Items][gtkstock], such as GTK_STOCK_OK or GTK_STOCK_OPEN. Named icons are easier to set up and therefore are more useful for new icons that an application wants to add, such as application icons or window icons.

  • Stock images can only be loaded at the symbolic sizes defined by the GtkIconSize enumeration, or by custom sizes defined by gtk_icon_size_register(), while named icons are more flexible and any pixel size can be specified.

  • Because stock images are closely tied to stock items, and thus to actions in the user interface, stock images may come in multiple variants for different widget states or writing directions.

A good rule of thumb is that if there is a stock image for what you want to use, use it, otherwise use a named icon. It turns out that internally stock images are generally defined in terms of one or more named icons. (An example of the more than one case is icons that depend on writing direction; GTK_STOCK_GO_FORWARD uses the two themed icons “gtk-stock-go-forward-ltr” and “gtk-stock-go-forward-rtl”.)

In many cases, named themes are used indirectly, via GtkImage or stock items, rather than directly, but looking up icons directly is also simple. The GtkIconTheme object acts as a database of all the icons in the current theme. You can create new GtkIconTheme objects, but it’s much more efficient to use the standard icon theme for the GdkScreen so that the icon information is shared with other people looking up icons.

GError *error = NULL;
GtkIconTheme *icon_theme;
GdkPixbuf *pixbuf;

icon_theme = gtk_icon_theme_get_default ();
pixbuf = gtk_icon_theme_load_icon (icon_theme,
                                   "my-icon-name", // icon name
                                   48, // icon size
                                   0,  // flags
                                   &error);
if (!pixbuf)
  {
    g_warning ("Couldn’t load icon: %s", error->message);
    g_error_free (error);
  }
else
  {
    // Use the pixbuf
    g_object_unref (pixbuf);
  }

Hierarchy

hierarchy this GtkIconTheme ancestor_0 GObject ancestor_0--this

Ancestors

Constructors

gtk_icon_theme_new

Creates a new icon theme object. Icon theme objects are used to lookup up an icon by name in a particular icon theme. Usually, you’ll want to use gtk_icon_theme_get_default() or gtk_icon_theme_get_for_screen() rather than creating a new icon theme object for scratch.

since: 2.4

Functions

gtk_icon_theme_add_builtin_icon

Registers a built-in icon for icon theme lookups. The idea of built-in icons is to allow an application or library that uses themed icons to function requiring files to be present in the file system. For instance, the default images for all of GTK+’s stock icons are registered as built-icons.

deprecated: 3.14 since: 2.4

gtk_icon_theme_get_default

Gets the icon theme for the default screen. See gtk_icon_theme_get_for_screen().

since: 2.4

gtk_icon_theme_get_for_screen

Gets the icon theme object associated with screen; if this function has not previously been called for the given screen, a new icon theme object will be created and associated with the screen. Icon theme objects are fairly expensive to create, so using this function is usually a better choice than calling than gtk_icon_theme_new() and setting the screen yourself; by using this function a single icon theme object will be shared between users.

since: 2.4

Instance methods

gtk_icon_theme_add_resource_path

Adds a resource path that will be looked at when looking for icons, similar to search paths.

since: 3.14

gtk_icon_theme_append_search_path

Appends a directory to the search path. See gtk_icon_theme_set_search_path().

since: 2.4

gtk_icon_theme_choose_icon

Looks up a named icon and returns a GtkIconInfo containing information such as the filename of the icon. The icon can then be rendered into a pixbuf using gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon() combines these two steps if all you need is the pixbuf.).

since: 2.12

gtk_icon_theme_choose_icon_for_scale

Looks up a named icon for a particular window scale and returns a GtkIconInfo containing information such as the filename of the icon. The icon can then be rendered into a pixbuf using gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon() combines these two steps if all you need is the pixbuf.).

since: 3.10

gtk_icon_theme_get_example_icon_name

Gets the name of an icon that is representative of the current theme (for instance, to use when presenting a list of themes to the user.).

since: 2.4

gtk_icon_theme_get_icon_sizes

Returns an array of integers describing the sizes at which the icon is available without scaling. A size of -1 means that the icon is available in a scalable format. The array is zero-terminated.

since: 2.6

gtk_icon_theme_get_search_path

Gets the current search path. See gtk_icon_theme_set_search_path().

since: 2.4

gtk_icon_theme_has_icon

Checks whether an icon theme includes an icon for a particular name.

since: 2.4

gtk_icon_theme_list_contexts

Gets the list of contexts available within the current hierarchy of icon themes. See gtk_icon_theme_list_icons() for details about contexts.

since: 2.12

gtk_icon_theme_list_icons

Lists the icons in the current icon theme. Only a subset of the icons can be listed by providing a context string. The set of values for the context string is system dependent, but will typically include such values as “Applications” and “MimeTypes”. Contexts are explained in the Icon Theme Specification. The standard contexts are listed in the Icon Naming Specification. Also see gtk_icon_theme_list_contexts().

since: 2.4

gtk_icon_theme_load_icon

Looks up an icon in an icon theme, scales it to the given size and renders it into a pixbuf. This is a convenience function; if more details about the icon are needed, use gtk_icon_theme_lookup_icon() followed by gtk_icon_info_load_icon().

since: 2.4

gtk_icon_theme_load_icon_for_scale

Looks up an icon in an icon theme for a particular window scale, scales it to the given size and renders it into a pixbuf. This is a convenience function; if more details about the icon are needed, use gtk_icon_theme_lookup_icon() followed by gtk_icon_info_load_icon().

since: 3.10

gtk_icon_theme_load_surface

Looks up an icon in an icon theme for a particular window scale, scales it to the given size and renders it into a cairo surface. This is a convenience function; if more details about the icon are needed, use gtk_icon_theme_lookup_icon() followed by gtk_icon_info_load_surface().

since: 3.10

gtk_icon_theme_lookup_by_gicon

Looks up an icon and returns a GtkIconInfo containing information such as the filename of the icon. The icon can then be rendered into a pixbuf using gtk_icon_info_load_icon().

since: 2.14

gtk_icon_theme_lookup_by_gicon_for_scale

Looks up an icon and returns a GtkIconInfo containing information such as the filename of the icon. The icon can then be rendered into a pixbuf using gtk_icon_info_load_icon().

since: 3.10

gtk_icon_theme_lookup_icon

Looks up a named icon and returns a GtkIconInfo containing information such as the filename of the icon. The icon can then be rendered into a pixbuf using gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon() combines these two steps if all you need is the pixbuf.).

since: 2.4

gtk_icon_theme_lookup_icon_for_scale

Looks up a named icon for a particular window scale and returns a GtkIconInfo containing information such as the filename of the icon. The icon can then be rendered into a pixbuf using gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon() combines these two steps if all you need is the pixbuf.).

since: 3.10

gtk_icon_theme_prepend_search_path

Prepends a directory to the search path. See gtk_icon_theme_set_search_path().

since: 2.4

gtk_icon_theme_rescan_if_needed

Checks to see if the icon theme has changed; if it has, any currently cached information is discarded and will be reloaded next time icon_theme is accessed.

since: 2.4

gtk_icon_theme_set_custom_theme

Sets the name of the icon theme that the GtkIconTheme object uses overriding system configuration. This function cannot be called on the icon theme objects returned from gtk_icon_theme_get_default() and gtk_icon_theme_get_for_screen().

since: 2.4

gtk_icon_theme_set_screen

Sets the screen for an icon theme; the screen is used to track the user’s currently configured icon theme, which might be different for different screens.

since: 2.4

gtk_icon_theme_set_search_path

Sets the search path for the icon theme object. When looking for an icon theme, GTK+ will search for a subdirectory of one or more of the directories in path with the same name as the icon theme containing an index.theme file. (Themes from multiple of the path elements are combined to allow themes to be extended by adding icons in the user’s home directory.).

since: 2.4

Methods inherited from GObject (43)

Please see GObject for a full list of methods.

Signals

Gtk.IconTheme::changed

Emitted when the current icon theme is switched or GTK+ detects that a change has occurred in the contents of the current icon theme.

Signals inherited from GObject (1)
GObject::notify

The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.

Class structure

struct GtkIconThemeClass {
  GObjectClass parent_class;
  void (* changed) (
    GtkIconTheme* icon_theme
  );
  void (* _gtk_reserved1) (
void
  );
  void (* _gtk_reserved2) (
void
  );
  void (* _gtk_reserved3) (
void
  );
  void (* _gtk_reserved4) (
void
  );
  
}

No description available.

Class members
parent_class: GObjectClass

The parent class.

changed: void (* changed) ( GtkIconTheme* icon_theme )

Signal emitted when the current icon theme is switched or GTK+ detects that a change has occurred in the contents of the current icon theme.

_gtk_reserved1: void (* _gtk_reserved1) ( void )

No description available.

_gtk_reserved2: void (* _gtk_reserved2) ( void )

No description available.

_gtk_reserved3: void (* _gtk_reserved3) ( void )

No description available.

_gtk_reserved4: void (* _gtk_reserved4) ( void )

No description available.

Virtual methods

Gtk.IconThemeClass.changed

Signal emitted when the current icon theme is switched or GTK+ detects that a change has occurred in the contents of the current icon theme.