Struct gtk::IconTheme

pub struct IconTheme(_, _);

IconTheme 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 IconSize enumeration, or by custom sizes defined by IconSize::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 Image or stock items, rather than directly, but looking up icons directly is also simple. The IconTheme object acts as a database of all the icons in the current theme. You can create new IconTheme objects, but it’s much more efficient to use the standard icon theme for the gdk::Screen 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);
  }

Implements

IconThemeExt, glib::object::ObjectExt

Implementations

impl IconTheme

pub fn new() -> IconTheme

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 IconTheme::get_default or IconTheme::get_for_screen rather than creating a new icon theme object for scratch.

Returns

the newly created IconTheme object.

pub fn get_default() -> Option<IconTheme>

Gets the icon theme for the default screen. See IconTheme::get_for_screen.

Returns

A unique IconTheme 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.

pub fn get_for_screen(screen: &Screen) -> Option<IconTheme>

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 IconTheme::new and setting the screen yourself; by using this function a single icon theme object will be shared between users.

screen

a gdk::Screen

Returns

A unique IconTheme 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.

Trait Implementations

impl Clone for IconTheme

fn clone(&self) -> IconTheme

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for IconTheme

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for IconTheme

fn default() -> Self

Returns the "default value" for a type.

impl Display for IconTheme

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for IconTheme

impl Hash for IconTheme

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl Ord for IconTheme

fn cmp(&self, other: &IconTheme) -> Ordering

This method returns an [Ordering] between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl<T: ObjectType> PartialEq<T> for IconTheme

fn eq(&self, other: &T) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<T: ObjectType> PartialOrd<T> for IconTheme

fn partial_cmp(&self, other: &T) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use]fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for IconTheme

fn static_type() -> Type

Returns the type identifier of Self.