## GtkIconTheme GtkIconTheme — Looking up icons by name |

## Synopsis

    #include <gtk/gtk.h>

                GtkIconInfo;
                GtkIconTheme;
    enum        GtkIconLookupFlags;
    #define     GTK_ICON_THEME_ERROR
    enum        GtkIconThemeError;
    GtkIconTheme* gtk_icon_theme_new            (void);
    GtkIconTheme* gtk_icon_theme_get_default    (void);
    GtkIconTheme* gtk_icon_theme_get_for_screen (GdkScreen *screen);
    void        gtk_icon_theme_set_screen       (GtkIconTheme *icon_theme,
                                                 GdkScreen *screen);
    void        gtk_icon_theme_set_search_path  (GtkIconTheme *icon_theme,
                                                 const gchar *path[],
                                                 gint n_elements);
    void        gtk_icon_theme_get_search_path  (GtkIconTheme *icon_theme,
                                                 gchar **path[],
                                                 gint *n_elements);
    void        gtk_icon_theme_append_search_path
                                                (GtkIconTheme *icon_theme,
                                                 const gchar *path);
    void        gtk_icon_theme_prepend_search_path
                                                (GtkIconTheme *icon_theme,
                                                 const gchar *path);
    void        gtk_icon_theme_set_custom_theme (GtkIconTheme *icon_theme,
                                                 const gchar *theme_name);
    gboolean    gtk_icon_theme_has_icon         (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name);
    GtkIconInfo* gtk_icon_theme_lookup_icon     (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name,
                                                 gint size,
                                                 GtkIconLookupFlags flags);
    GdkPixbuf*  gtk_icon_theme_load_icon        (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name,
                                                 gint size,
                                                 GtkIconLookupFlags flags,
                                                 GError **error);
    GList*      gtk_icon_theme_list_icons       (GtkIconTheme *icon_theme,
                                                 const gchar *context);
    gint*       gtk_icon_theme_get_icon_sizes   (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name);
    char*       gtk_icon_theme_get_example_icon_name
                                                (GtkIconTheme *icon_theme);
    gboolean    gtk_icon_theme_rescan_if_needed (GtkIconTheme *icon_theme);
    void        gtk_icon_theme_add_builtin_icon (const gchar *icon_name,
                                                 gint size,
                                                 GdkPixbuf *pixbuf);
    GtkIconInfo* gtk_icon_info_copy             (GtkIconInfo *icon_info);
    void        gtk_icon_info_free              (GtkIconInfo *icon_info);
    gint        gtk_icon_info_get_base_size     (GtkIconInfo *icon_info);
    const gchar* gtk_icon_info_get_filename     (GtkIconInfo *icon_info);
    GdkPixbuf*  gtk_icon_info_get_builtin_pixbuf
                                                (GtkIconInfo *icon_info);
    GdkPixbuf*  gtk_icon_info_load_icon         (GtkIconInfo *icon_info,
                                                 GError **error);
    void        gtk_icon_info_set_raw_coordinates
                                                (GtkIconInfo *icon_info,
                                                 gboolean raw_coordinates);
    gboolean    gtk_icon_info_get_embedded_rect (GtkIconInfo *icon_info,
                                                 GdkRectangle *rectangle);
    gboolean    gtk_icon_info_get_attach_points (GtkIconInfo *icon_info,
                                                 GdkPoint **points,
                                                 gint *n_points);
    const gchar* gtk_icon_info_get_display_name (GtkIconInfo *icon_info);

## Object Hierarchy

      GObject
       +----GtkIconTheme

## Signals

    "changed"   void        user_function      (GtkIconTheme *icon_theme,
                                                gpointer      user_data)       : Run last

## Description

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 selecetd by the user. The operation of icon themes on Linux and Unix follows the Icon Theme Specification. There is a default icon theme, named `hicolor` where applications should install their icons, but more additional application themes can be installed as operating system vendors and users choose.

Named icons are similar to the Themeable Stock Images(3) facility, 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(3)., 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 its 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. In the case where the default screen is being used, looking up an icon can be as simple as:

    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, /* size */
                                       0,  /* flags */
                                       &error);
    if (!pixbuf)
      {
        g_warning ("Couldn't load icon: %s", error->message);
        g_error_free (message);
      }
    else
      {
        /* Use the pixbuf */
        g_object_unref (pixbuf);
      }

## Details

### GtkIconInfo

    typedef struct _GtkIconInfo GtkIconInfo;

Contains information found when looking up an icon in an icon theme.

### GtkIconTheme

    typedef struct _GtkIconTheme GtkIconTheme;

Acts as a database of information about an icon theme. Normally, you retrieve the icon theme for a particular screen using `gtk_icon_theme_get_for_screen()` and it will contain information about current icon theme for that screen, but you can also create a new GtkIconTheme object and set the icon theme name explicitely using `gtk_icon_theme_set_custom_theme()`.

### enum GtkIconLookupFlags

    typedef enum
    {
      GTK_ICON_LOOKUP_NO_SVG = 1 << 0,
      GTK_ICON_LOOKUP_FORCE_SVG = 1 << 1,
      GTK_ICON_LOOKUP_USE_BUILTIN = 1 << 2
    } GtkIconLookupFlags;

Used to specify options for `gtk_icon_theme_lookup_icon()`

`GTK_ICON_LOOKUP_NO_SVG` | Never return SVG icons, even if gdk-pixbuf supports them. Cannot be used together with `GTK_ICON_LOOKUP_FORCE_SVG`.
`GTK_ICON_LOOKUP_FORCE_SVG` | Return SVG icons, even if gdk-pixbuf doesn't support them. Cannot be used together with `GTK_ICON_LOOKUP_NO_SVG`.
`GTK_ICON_LOOKUP_USE_BUILTIN` | When passed to `gtk_icon_theme_lookup_icon()` includes builtin icons as well as files. For a builtin icon, `gtk_icon_info_get_filename()` returns `NULL` and you need to call `gtk_icon_info_get_builtin_pixbuf()`.

### GTK_ICON_THEME_ERROR

    #define GTK_ICON_THEME_ERROR gtk_icon_theme_error_quark ()

### enum GtkIconThemeError

    typedef enum {
      GTK_ICON_THEME_NOT_FOUND,
      GTK_ICON_THEME_FAILED
    } GtkIconThemeError;

Error codes for GtkIconTheme operations.

`GTK_ICON_THEME_NOT_FOUND` | The icon specified does not exist in the theme
`GTK_ICON_THEME_FAILED` | An unspecified error occurred.

### gtk_icon_theme_new ()

    GtkIconTheme* gtk_icon_theme_new            (void);

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.

Returns : | the newly created GtkIconTheme object.

Since 2.4

### gtk_icon_theme_get_default ()

    GtkIconTheme* gtk_icon_theme_get_default    (void);

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

Returns : | A unique GtkIconTheme associated with the default screen. This icon theme is associated with the screen and can be used as long as the screen is open. Do not ref or unref it.

Since 2.4

### gtk_icon_theme_get_for_screen ()

    GtkIconTheme* gtk_icon_theme_get_for_screen (GdkScreen *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.

`screen` : | a GdkScreen
Returns : | A unique GtkIconTheme associated with the given screen. This icon theme is associated with the screen and can be used as long as the screen is open. Do not ref or unref it.

Since 2.4

### gtk_icon_theme_set_screen ()

    void        gtk_icon_theme_set_screen       (GtkIconTheme *icon_theme,
                                                 GdkScreen *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.

`icon_theme` : | a GtkIconTheme
`screen` : | a GdkScreen

Since 2.4

### gtk_icon_theme_set_search_path ()

    void        gtk_icon_theme_set_search_path  (GtkIconTheme *icon_theme,
                                                 const gchar *path[],
                                                 gint n_elements);

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. (Themes from multiple of the path elements are combined to allow themes to be extended by adding icons in the user's home directory.)

In addition if an icon found isn't found either in the current icon theme or the default icon theme, and an image file with the right name is found directly in one of the elements of `path`, then that image will be used for the icon name. (This is legacy feature, and new icons should be put into the default icon theme, which is called DEFAULT_THEME_NAME, rather than directly on the icon path.)

`icon_theme` : | a GtkIconTheme
`path` : | array of directories that are searched for icon themes
`n_elements` : | number of elements in `path`.

Since 2.4

### gtk_icon_theme_get_search_path ()

    void        gtk_icon_theme_get_search_path  (GtkIconTheme *icon_theme,
                                                 gchar **path[],
                                                 gint *n_elements);

Gets the current search path. See `gtk_icon_theme_set_search_path()`.

`icon_theme` : | a GtkIconTheme
`path` : | location to store a list of icon theme path directories or `NULL` The stored value should be freed with `g_strfreev()`.
`n_elements` : | location to store number of elements in `path`, or `NULL`

Since 2.4

### gtk_icon_theme_append_search_path ()

    void        gtk_icon_theme_append_search_path
                                                (GtkIconTheme *icon_theme,
                                                 const gchar *path);

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

`icon_theme` : | a GtkIconTheme
`path` : | directory name to append to the icon path

Since 2.4

### gtk_icon_theme_prepend_search_path ()

    void        gtk_icon_theme_prepend_search_path
                                                (GtkIconTheme *icon_theme,
                                                 const gchar *path);

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

`icon_theme` : | a GtkIconTheme
`path` : | directory name to prepend to the icon path

Since 2.4

### gtk_icon_theme_set_custom_theme ()

    void        gtk_icon_theme_set_custom_theme (GtkIconTheme *icon_theme,
                                                 const gchar *theme_name);

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()`.

`icon_theme` : | a GtkIconTheme
`theme_name` : | name of icon theme to use instead of configured theme, or `NULL` to unset a previously set custom theme

Since 2.4

### gtk_icon_theme_has_icon ()

    gboolean    gtk_icon_theme_has_icon         (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name);

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

`icon_theme` : | a GtkIconTheme
`icon_name` : | the name of an icon
Returns : | `TRUE` if `icon_theme` includes an icon for `icon_name`.

Since 2.4

### gtk_icon_theme_lookup_icon ()

    GtkIconInfo* gtk_icon_theme_lookup_icon     (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name,
                                                 gint size,
                                                 GtkIconLookupFlags flags);

Looks up a named icon and returns a structure 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.)

`icon_theme` : | a GtkIconTheme
`icon_name` : | the name of the icon to lookup
`size` : | desired icon size
`flags` : | flags modifying the behavior of the icon lookup
Returns : | a GtkIconInfo structure containing information about the icon, or `NULL` if the icon wasn't found. Free with `gtk_icon_info_free()`

Since 2.4

### gtk_icon_theme_load_icon ()

    GdkPixbuf*  gtk_icon_theme_load_icon        (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name,
                                                 gint size,
                                                 GtkIconLookupFlags flags,
                                                 GError **error);

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()`.

Note that you probably want to listen for icon theme changes and update the icon. This is usually done by connecting to the GtkWidget::style-set signal. If for some reason you do not want to update the icon when the icon theme changes, you should consider using `gdk_pixbuf_copy()` to make a private copy of the pixbuf returned by this function. Otherwise GTK+ may need to keep the old icon theme loaded, which would be a waste of memory.

`icon_theme` : | a GtkIconTheme
`icon_name` : | the name of the icon to lookup
`size` : | the desired icon size. The resulting icon may not be exactly this size; see `gtk_icon_info_load_icon()`.
`flags` : | flags modifying the behavior of the icon lookup
`error` : | Location to store error information on failure, or `NULL`.
Returns : | the rendered icon; this may be a newly created icon or a new reference to an internal icon, so you must not modify the icon. Use `g_object_unref()` to release your reference to the icon. `NULL` if the icon isn't found.

Since 2.4

### gtk_icon_theme_list_icons ()

    GList*      gtk_icon_theme_list_icons       (GtkIconTheme *icon_theme,
                                                 const gchar *context);

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".

`icon_theme` : | a GtkIconTheme
`context` : | a string identifying a particular type of icon, or `NULL` to list all icons.
Returns : | a GList list holding the names of all the icons in the theme. You must first free each element in the list with `g_free()`, then free the list itself with `g_list_free()`.

Since 2.4

### gtk_icon_theme_get_icon_sizes ()

    gint*       gtk_icon_theme_get_icon_sizes   (GtkIconTheme *icon_theme,
                                                 const gchar *icon_name);

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.

`icon_theme` : | a GtkIconTheme
`icon_name` : | the name of an icon
Returns : | An newly allocated array describing the sizes at which the icon is available. The array should be freed with `g_free()` when it is no longer needed.

Since 2.6

### gtk_icon_theme_get_example_icon_name ()

    char*       gtk_icon_theme_get_example_icon_name
                                                (GtkIconTheme *icon_theme);

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.)

`icon_theme` : | a GtkIconTheme
Returns : | the name of an example icon or `NULL`. Free with `g_free()`.

Since 2.4

### gtk_icon_theme_rescan_if_needed ()

    gboolean    gtk_icon_theme_rescan_if_needed (GtkIconTheme *icon_theme);

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.

`icon_theme` : | a GtkIconTheme
Returns : | `TRUE` if the icon theme has changed and needed to be reloaded.

Since 2.4

### gtk_icon_theme_add_builtin_icon ()

    void        gtk_icon_theme_add_builtin_icon (const gchar *icon_name,
                                                 gint size,
                                                 GdkPixbuf *pixbuf);

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.

In general, if you use `gtk_icon_theme_add_builtin_icon()` you should also install the icon in the icon theme, so that the icon is generally available.

This function will generally be used with pixbufs loaded via `gdk_pixbuf_new_from_inline()`.

`icon_name` : | the name of the icon to register
`size` : | the size at which to register the icon (different images can be registered for the same icon name at different sizes.)
`pixbuf` : | GdkPixbuf that contains the image to use for `icon_name`.

Since 2.4

### gtk_icon_info_copy ()

    GtkIconInfo* gtk_icon_info_copy             (GtkIconInfo *icon_info);

Make a copy of a GtkIconInfo.

`icon_info` : | a GtkIconInfo
Returns : | the new GtkIconInfo

Since 2.4

### gtk_icon_info_free ()

    void        gtk_icon_info_free              (GtkIconInfo *icon_info);

Free a GtkIconInfo and associated information

`icon_info` : | a GtkIconInfo

Since 2.4

### gtk_icon_info_get_base_size ()

    gint        gtk_icon_info_get_base_size     (GtkIconInfo *icon_info);

Gets the base size for the icon. The base size is a size for the icon that was specified by the icon theme creator. This may be different than the actual size of image; an example of this is small emblem icons that can be attached to a larger icon. These icons will be given the same base size as the larger icons to which they are attached.

`icon_info` : | a GtkIconInfo
Returns : | the base size, or 0, if no base size is known for the icon.

Since 2.4

### gtk_icon_info_get_filename ()

    const gchar* gtk_icon_info_get_filename     (GtkIconInfo *icon_info);

Gets the filename for the icon. If the `GTK_ICON_LOOKUP_USE_BUILTIN` flag was passed to `gtk_icon_theme_lookup_icon()`, there may be no filename if a builtin icon is returned; in this case, you should use `gtk_icon_info_get_builtin_pixbuf()`.

`icon_info` : | a GtkIconInfo
Returns : | the filename for the icon, or `NULL` if `gtk_icon_info_get_builtin_pixbuf()` should be used instead. The return value is owned by GTK+ and should not be modified or freed.

Since 2.4

### gtk_icon_info_get_builtin_pixbuf ()

    GdkPixbuf*  gtk_icon_info_get_builtin_pixbuf
                                                (GtkIconInfo *icon_info);

Gets the built-in image for this icon, if any. To allow GTK+ to use built in icon images, you must pass the `GTK_ICON_LOOKUP_USE_BUILTIN` to `gtk_icon_theme_lookup_icon()`.

`icon_info` : | a GtkIconInfo structure
Returns : | the built-in image pixbuf, or `NULL`. No extra reference is added to the returned pixbuf, so if you want to keep it around, you must use `g_object_ref()`. The returned image must not be modified.

Since 2.4

### gtk_icon_info_load_icon ()

    GdkPixbuf*  gtk_icon_info_load_icon         (GtkIconInfo *icon_info,
                                                 GError **error);

Renders an icon previously looked up in an icon theme using `gtk_icon_theme_lookup_icon()`; the size will be based on the size passed to `gtk_icon_theme_lookup_icon()`. Note that the resulting pixbuf may not be exactly this size; an icon theme may have icons that differ slightly from their nominal sizes, and in addition GTK+ will avoid scaling icons that it considers sufficiently close to the requested size or for which the source image would have to be scaled up too far. (This maintains sharpness.)

`icon_info` : | a GtkIconInfo structure from `gtk_icon_theme_lookup_icon()`
`error` : | location to store error information on failure, or `NULL`.
Returns : | the rendered icon; this may be a newly created icon or a new reference to an internal icon, so you must not modify the icon. Use `g_object_unref()` to release your reference to the icon.

Since 2.4

### gtk_icon_info_set_raw_coordinates ()

    void        gtk_icon_info_set_raw_coordinates
                                                (GtkIconInfo *icon_info,
                                                 gboolean raw_coordinates);

Sets whether the coordinates returned by `gtk_icon_info_get_embedded_rect()` and `gtk_icon_info_get_attach_points()` should be returned in their original form as specified in the icon theme, instead of scaled appropriately for the pixbuf returned by `gtk_icon_info_load_icon()`.

Raw coordinates are somewhat strange; they are specified to be with respect to the unscaled pixmap for PNG and XPM icons, but for SVG icons, they are in a 1000x1000 coordinate space that is scaled to the final size of the icon. You can determine if the icon is an SVG icon by using `gtk_icon_info_get_filename()`, and seeing if it is non-`NULL` and ends in '.svg'.

This function is provided primarily to allow compatibility wrappers for older API's, and is not expected to be useful for applications.

`icon_info` : | a GtkIconInfo
`raw_coordinates` : | whether the coordinates of embedded rectangles and attached points should be returned in their original (unscaled) form.

Since 2.4

### gtk_icon_info_get_embedded_rect ()

    gboolean    gtk_icon_info_get_embedded_rect (GtkIconInfo *icon_info,
                                                 GdkRectangle *rectangle);

Gets the coordinates of a rectangle within the icon that can be used for display of information such as a preview of the contents of a text file. See `gtk_icon_info_set_raw_coordinates()` for further information about the coordinate system.

`icon_info` : | a GtkIconInfo
`rectangle` : | GdkRectangle in which to store embedded rectangle coordinates; coordinates are only stored when this function returns `TRUE`.
Returns : | `TRUE` if the icon has an embedded rectangle

Since 2.4

### gtk_icon_info_get_attach_points ()

    gboolean    gtk_icon_info_get_attach_points (GtkIconInfo *icon_info,
                                                 GdkPoint **points,
                                                 gint *n_points);

Fetches the set of attach points for an icon. An attach point is a location in the icon that can be used as anchor points for attaching emblems or overlays to the icon.

`icon_info` : | a GtkIconInfo
`points` : | location to store pointer to an array of points, or `NULL` free the array of points with `g_free()`.
`n_points` : | location to store the number of points in `points`, or `NULL`
Returns : | `TRUE` if there are any attach points for the icon.

Since 2.4

### gtk_icon_info_get_display_name ()

    const gchar* gtk_icon_info_get_display_name (GtkIconInfo *icon_info);

Gets the display name for an icon. A display name is a string to be used in place of the icon name in a user visible context like a list of icons.

`icon_info` : | a GtkIconInfo
Returns : | the display name for the icon or `NULL`, if the icon doesn't have a specified display name. This value is owned `icon_info` and must not be modified or free.

Since 2.4

## Signal Details

### The "changed" signal

    void        user_function                  (GtkIconTheme *icon_theme,
                                                gpointer      user_data)       : Run last

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

`icon_theme` : | the icon theme
`user_data` : | user data set when the signal handler was connected.