IconThemeProtocol

public protocol IconThemeProtocol : ObjectProtocol

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, 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, 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. (C Language Example):

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);
  }

The IconThemeProtocol protocol exposes the methods and properties of an underlying GtkIconTheme instance. The default implementation of these can be found in the protocol extension below. For a concrete class that implements these methods and properties, see IconTheme. Alternatively, use IconThemeRef as a lighweight, unowned reference if you already have an instance you just want to use.

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  • ptr

    Untyped pointer to the underlying GtkIconTheme instance.

    Declaration

    Swift

    var ptr: UnsafeMutableRawPointer! { get }
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  • icon_theme_ptr Default implementation

    Typed pointer to the underlying GtkIconTheme instance.

    Default Implementation

    Return the stored, untyped pointer as a typed pointer to the GtkIconTheme instance.

    Declaration

    Swift

    var icon_theme_ptr: UnsafeMutablePointer<GtkIconTheme>! { get }
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  • Required Initialiser for types conforming to IconThemeProtocol

    Declaration

    Swift

    init(raw: UnsafeMutableRawPointer)
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IconTheme signals

  • Connect a Swift signal handler to the given, typed IconThemeSignalName signal

    Declaration

    Swift

    @discardableResult
@inlinable
func connect(signal s: IconThemeSignalName, flags f: ConnectFlags = ConnectFlags(0), handler h: @escaping SignalHandler) -> Int

    Parameters

    signal

    The signal to connect
    flags

    The connection flags to use
    data

    A pointer to user data to provide to the callback
    destroyData

    A GClosureNotify C function to destroy the data pointed to by userData
    handler

    The Swift signal handler (function or callback) to invoke on the given signal

    Return Value

    The signal handler ID (always greater than 0 for successful connections)

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  • Connect a C signal handler to the given, typed IconThemeSignalName signal

    Declaration

    Swift

    @discardableResult
@inlinable
func connect(signal s: IconThemeSignalName, flags f: ConnectFlags = ConnectFlags(0), data userData: gpointer!, destroyData destructor: GClosureNotify? = nil, signalHandler h: @escaping GCallback) -> Int

    Parameters

    signal

    The signal to connect
    flags

    The connection flags to use
    data

    A pointer to user data to provide to the callback
    destroyData

    A GClosureNotify C function to destroy the data pointed to by userData
    signalHandler

    The C function to be called on the given signal

    Return Value

    The signal handler ID (always greater than 0 for successful connections)

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  • onChanged(flags:handler:) Extension method

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

    Note

    This represents the underlying changed signal

    Declaration

    Swift

    @discardableResult
@inlinable
func onChanged(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: IconThemeRef) -> Void) -> Int

    Parameters

    flags

    Flags
    unownedSelf

    Reference to instance of self
    handler

    The signal handler to call Run the given callback whenever the changed signal is emitted
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  • changedSignal Extension method

    Typed changed signal for using the connect(signal:) methods

    Declaration

    Swift

    static var changedSignal: IconThemeSignalName { get }
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IconTheme Class: IconThemeProtocol extension (methods and fields)

  • addResource(path:) Extension method

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

    This function should be used to make application-specific icons available as part of the icon theme.

    The resources are considered as part of the hicolor icon theme and must be located in subdirectories that are defined in the hicolor icon theme, such as `path/16x16/actions/run.png`. Icons that are directly placed in the resource path instead of a subdirectory are also considered as ultimate fallback.

    Declaration

    Swift

    @inlinable
func addResource(path: UnsafePointer<gchar>!)
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  • appendSearch(path:) Extension method

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

    Declaration

    Swift

    @inlinable
func appendSearch(path: UnsafePointer<gchar>!)
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  • 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.)

    If icon_names contains more than one name, this function tries them all in the given order before falling back to inherited icon themes.

    Declaration

    Swift

    @inlinable
func chooseIcon(iconNames: UnsafeMutablePointer<UnsafePointer<gchar>?>!, size: Int, flags: IconLookupFlags) -> IconInfoRef!
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  • 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.)

    If icon_names contains more than one name, this function tries them all in the given order before falling back to inherited icon themes.

    Declaration

    Swift

    @inlinable
func chooseIconForScale(iconNames: UnsafeMutablePointer<UnsafePointer<gchar>?>!, size: Int, scale: Int, flags: IconLookupFlags) -> IconInfoRef!
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  • getExampleIconName() Extension method

    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.)

    Declaration

    Swift

    @inlinable
func getExampleIconName() -> String!
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  • getIconSizes(iconName:) Extension method

    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.

    Declaration

    Swift

    @inlinable
func getIconSizes(iconName: UnsafePointer<gchar>!) -> UnsafeMutablePointer<gint>!
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  • getSearch(path:nElements:) Extension method

    Gets the current search path. See gtk_icon_theme_set_search_path().

    Declaration

    Swift

    @inlinable
func getSearch(path: UnsafeMutablePointer<UnsafeMutablePointer<UnsafeMutablePointer<gchar>?>?>! = nil, nElements: UnsafeMutablePointer<gint>!)
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  • hasIcon(iconName:) Extension method

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

    Declaration

    Swift

    @inlinable
func hasIcon(iconName: UnsafePointer<gchar>!) -> Bool
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  • listContexts() Extension method

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

    Declaration

    Swift

    @inlinable
func listContexts() -> GLib.ListRef!
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  • listIcons(context:) Extension method

    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().

    Declaration

    Swift

    @inlinable
func listIcons(context: UnsafePointer<gchar>? = nil) -> GLib.ListRef!
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  • 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 GtkWidgetstyle-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.

    Declaration

    Swift

    @inlinable
func loadIcon(iconName: UnsafePointer<gchar>!, size: Int, flags: IconLookupFlags) throws -> PixbufRef!
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  • 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().

    Note that you probably want to listen for icon theme changes and update the icon. This is usually done by connecting to the GtkWidgetstyle-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.

    Declaration

    Swift

    @inlinable
func loadIconForScale(iconName: UnsafePointer<gchar>!, size: Int, scale: Int, flags: IconLookupFlags) throws -> PixbufRef!
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  • 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().

    Note that you probably want to listen for icon theme changes and update the icon. This is usually done by connecting to the GtkWidgetstyle-set signal.

    Declaration

    Swift

    @inlinable
func loadSurface(iconName: UnsafePointer<gchar>!, size: Int, scale: Int, for window: Gdk.WindowRef? = nil, flags: IconLookupFlags) throws -> Cairo.SurfaceRef!
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  • 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().

    Note that you probably want to listen for icon theme changes and update the icon. This is usually done by connecting to the GtkWidgetstyle-set signal.

    Declaration

    Swift

    @inlinable
func loadSurface<WindowT>(iconName: UnsafePointer<gchar>!, size: Int, scale: Int, for window: WindowT?, flags: IconLookupFlags) throws -> Cairo.SurfaceRef! where WindowT : WindowProtocol
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  • 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().

    When rendering on displays with high pixel densities you should not use a size multiplied by the scaling factor returned by functions like gdk_window_get_scale_factor(). Instead, you should use gtk_icon_theme_lookup_by_gicon_for_scale(), as the assets loaded for a given scaling factor may be different.

    Declaration

    Swift

    @inlinable
func lookupByIcon<IconT>(icon: IconT, size: Int, flags: IconLookupFlags) -> IconInfoRef! where IconT : IconProtocol
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  • 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().

    Declaration

    Swift

    @inlinable
func lookupByIconForScale<IconT>(icon: IconT, size: Int, scale: Int, flags: IconLookupFlags) -> IconInfoRef! where IconT : IconProtocol
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  • 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.)

    When rendering on displays with high pixel densities you should not use a size multiplied by the scaling factor returned by functions like gdk_window_get_scale_factor(). Instead, you should use gtk_icon_theme_lookup_icon_for_scale(), as the assets loaded for a given scaling factor may be different.

    Declaration

    Swift

    @inlinable
func lookupIcon(iconName: UnsafePointer<gchar>!, size: Int, flags: IconLookupFlags) -> IconInfoRef!
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  • 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.)

    Declaration

    Swift

    @inlinable
func lookupIconForScale(iconName: UnsafePointer<gchar>!, size: Int, scale: Int, flags: IconLookupFlags) -> IconInfoRef!
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  • prependSearch(path:) Extension method

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

    Declaration

    Swift

    @inlinable
func prependSearch(path: UnsafePointer<gchar>!)
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  • rescanIfNeeded() Extension method

    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.

    Declaration

    Swift

    @inlinable
func rescanIfNeeded() -> Bool
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  • setCustomTheme(themeName:) Extension method

    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().

    Declaration

    Swift

    @inlinable
func setCustomTheme(themeName: UnsafePointer<gchar>? = nil)
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  • set(screen:) Extension method

    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.

    Declaration

    Swift

    @inlinable
func set<ScreenT>(screen: ScreenT) where ScreenT : ScreenProtocol
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  • setSearch(path:nElements:) Extension method

    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.)

    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 fallback icon theme, which is called hicolor, rather than directly on the icon path.)

    Declaration

    Swift

    @inlinable
func setSearch(path: UnsafeMutablePointer<UnsafePointer<gchar>?>!, nElements: Int)
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  • exampleIconName Extension method

    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.)

    Declaration

    Swift

    @inlinable
var exampleIconName: String! { get }
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