Class (GI Class)

St-18StThemeNode

Style information for one node in a tree of themed objects

A St.ThemeNode represents the CSS style information (the set of CSS properties) for one node in a tree of themed objects. In typical usage, it represents the style information for a single Clutter.Actor. A St.ThemeNode is immutable: attributes such as the CSS classes for the node are passed in at construction. If the attributes of the node or any parent node change, the node should be discarded and a new node created. St.ThemeNode has generic accessors to look up properties by name and specific accessors for standard CSS properties that add caching and handling of various details of the CSS specification. St.ThemeNode also has convenience functions to help in implementing a Clutter.Actor with borders and padding.

Note that pixel measurements take the St.ThemeContext.scale_factor into account so all values are in physical pixels, as opposed to logical pixels. Physical pixels correspond to actor sizes, not necessarily to pixels on display devices (eg. when scale-monitor-framebuffer is enabled).

Hierarchy (View Summary)

Index

Constructors

Properties

Methods

Methods - Inherited from GObject

Constructors

Properties

Compile-time signal type information.

This instance property is generated only for TypeScript type checking. It is not defined at runtime and should not be accessed in JS code.

$gtype: GType<St.ThemeNode>

Methods

  • Adjusts a "for height" passed to clutter_actor_get_preferred_width() to account for borders and padding. This is a convenience function meant to be called from a get_preferred_width() method of a Clutter.Actor subclass. The value after adjustment is the height available for the actor's content.

    Parameters

    • for_height: number

      the "for height" to adjust

    Returns number

  • Adjusts a "for width" passed to clutter_actor_get_preferred_height() to account for borders and padding. This is a convenience function meant to be called from a get_preferred_height() method of a Clutter.Actor subclass. The value after adjustment is the width available for the actor's content.

    Parameters

    • for_width: number

      the "for width" to adjust

    Returns number

  • Adjusts the minimum and natural height computed for an actor by adding on the necessary space for borders and padding and taking into account any minimum or maximum height. This is a convenience function meant to be called from the get_preferred_height() method of a Clutter.Actor subclass

    Parameters

    • min_height_p: number

      the minimum height to adjust

    • natural_height_p: number

      the natural height to adjust

    Returns [number, number]

  • Adjusts the minimum and natural width computed for an actor by adding on the necessary space for borders and padding and taking into account any minimum or maximum width. This is a convenience function meant to be called from the get_preferred_width() method of a Clutter.Actor subclass

    Parameters

    • min_width_p: number

      the minimum width to adjust

    • natural_width_p: number

      the natural width to adjust

    Returns [number, number]

  • Compare two StThemeNodes. Two nodes which compare equal will match the same CSS rules and have the same style properties. However, two nodes that have ended up with identical style properties do not necessarily compare equal.

    In detail, node_a and node_b are considered equal if and only if:

    • they share the same St.Theme and St.ThemeContext
    • they have the same parent
    • they have the same element type
    • their id, class, pseudo-class and inline-style match

    Parameters

    Returns boolean

    true if node_a equals node_b

  • Tests if two theme nodes have the same borders and padding; this can be used to optimize having to relayout when the style applied to a Clutter actor changes colors without changing the geometry.

    Parameters

    Returns boolean

    true if equal, false otherwise

  • Gets the value for the -st-background-image-shadow style property

    Returns St.Shadow | null

    the node's background image shadow, or null if node has no such shadow

  • Get the border width for node on side, in physical pixels.

    Parameters

    Returns number

    the border width in physical pixels

  • Gets the value for the box-shadow style property

    Returns St.Shadow | null

    the node's shadow, or null if node has no shadow

  • Generically looks up a property containing a single color value. When specific getters (like st_theme_node_get_background_color()) exist, they should be used instead. They are cached, so more efficient, and have handling for shortcut properties and other details of CSS.

    If property_name is not found, a warning will be logged and a default color returned.

    See also st_theme_node_lookup_color(), which provides more options, and lets you handle the case where the theme does not specify the indicated color.

    Parameters

    • property_name: string

      The name of the color property

    Returns Cogl.Color

  • Gets the box within an actor's allocation that contents the content of an actor (excluding borders and padding). This is a convenience function meant to be used from the allocate() or paint() methods of a Clutter.Actor subclass.

    Parameters

    • allocation: ActorBox

      the box allocated to a ClutterAlctor

    Returns ActorBox

  • Generically looks up a property containing a single numeric value without units.

    See also st_theme_node_lookup_double(), which provides more options, and lets you handle the case where the theme does not specify the indicated value.

    Parameters

    • property_name: string

      The name of the numeric property

    Returns number

    the value found. If property_name is not found, a warning will be logged and 0 will be returned.

  • Get the list of element classes for node.

    Returns string[]

    the element's classes

  • Get the unique element ID for node.

    Returns string

    the element's ID

  • Get the CSS font-features for node.

    Returns string

    font-features as a string

  • Get the height for node, in physical pixels.

    Returns number

    the height in physical pixels

  • Gets the total horizontal padding (left + right padding), in physical pixels.

    Returns number

    the total horizontal padding in physical pixels

  • Gets the colors that should be used for colorizing symbolic icons according the style of this node.

    Returns IconColors

    the icon colors to use for this theme node

  • Get the icon style for node (eg. symbolic, regular). This corresponds to the special -st-icon-style CSS property.

    Returns St.IconStyle

    the icon style for node

  • Generically looks up a property containing a single length value. When specific getters (like st_theme_node_get_border_width()) exist, they should be used instead. They are cached, so more efficient, and have handling for shortcut properties and other details of CSS.

    Unlike st_theme_node_get_color() and st_theme_node_get_double(), this does not print a warning if the property is not found; it just returns 0.

    See also st_theme_node_lookup_length(), which provides more options. The returned value is in physical pixels, as opposed to logical pixels.

    Parameters

    • property_name: string

      The name of the length property

    Returns number

    the length, in pixels, or 0 if the property was not found.

  • Gets the value for the letter-spacing style property, in physical pixels.

    Returns number

    the value of the letter-spacing property, if found, or zero if such property has not been found.

  • Get the margin for node on side, in physical pixels. This corresponds to the CSS properties such as margin-top.

    Parameters

    Returns number

    the margin size in physical pixels

  • Get the maximum height for node, in physical pixels.

    Returns number

    the maximum height in physical pixels

  • Get the maximum width for node, in physical pixels.

    Returns number

    the maximum width in physical pixels

  • Get the minimum height for node, in physical pixels.

    Returns number

    the minimum height in physical pixels

  • Get the minimum width for node, in physical pixels.

    Returns number

    the minimum width in physical pixels

  • Get the width of the outline for node, in physical pixels.

    Returns number

    the width in physical pixels

  • Get the padding for node on side, in physical pixels. This corresponds to the CSS properties such as padding-top.

    Parameters

    Returns number

    the padding size in physical pixels

  • Gets the box used to paint the actor, including the area occupied by properties which paint outside the actor's assigned allocation. When painting node to an offscreen buffer, this function can be used to determine the necessary size of the buffer.

    Parameters

    Returns ActorBox

  • Get the list of pseudo-classes for node (eg. :focused).

    Returns string[]

    the element's pseudo-classes

  • Generically looks up a property containing a set of shadow values. When specific getters (like st_theme_node_get_box_shadow()) exist, they should be used instead. They are cached, so more efficient, and have handling for shortcut properties and other details of CSS.

    Like st_theme_get_length(), this does not print a warning if the property is not found; it just returns null

    See also st_theme_node_lookup_shadow (), which provides more options.

    Parameters

    • property_name: string

      The name of the shadow property

    Returns St.Shadow | null

    the shadow, or null if the property was not found.

  • Gets the value for the text-shadow style property

    Returns St.Shadow | null

    the node's text-shadow, or null if node has no text-shadow

  • Get the value of the transition-duration property, which specifies the transition time between the previous St.ThemeNode and node.

    Returns number

    the node's transition duration in milliseconds

  • Looks up a property containing a single URL value.

    See also st_theme_node_lookup_url(), which provides more options, and lets you handle the case where the theme does not specify the indicated value.

    Parameters

    • property_name: string

      The name of the string property

    Returns Gio.File | null

    the newly allocated value if found. If property_name is not found, a warning will be logged and null will be returned.

  • Gets the total vertical padding (top + bottom padding), in physical pixels.

    Returns number

    the total vertical padding in physical pixels

  • Get the width for node, in physical pixels.

    Returns number

    the width in physical pixels

  • Converts node to a hash value.

    Returns number

    a hash value corresponding to node

  • Generically looks up a property containing a single color value. When specific getters (like st_theme_node_get_background_color()) exist, they should be used instead. They are cached, so more efficient, and have handling for shortcut properties and other details of CSS.

    See also st_theme_node_get_color(), which provides a simpler API.

    Parameters

    • property_name: string

      The name of the color property

    • inherit: boolean

      if true, if a value is not found for the property on the node, then it will be looked up on the parent node, and then on the parent's parent, and so forth. Note that if the property has a value of 'inherit' it will be inherited even if false is passed in for inherit; this only affects the default behavior for inheritance.

    Returns [boolean, Cogl.Color]

    true if the property was found in the properties for this theme node (or in the properties of parent nodes when inheriting.)

  • Generically looks up a property containing a single numeric value without units.

    See also st_theme_node_get_double(), which provides a simpler API.

    Parameters

    • property_name: string

      The name of the numeric property

    • inherit: boolean

      if true, if a value is not found for the property on the node, then it will be looked up on the parent node, and then on the parent's parent, and so forth. Note that if the property has a value of 'inherit' it will be inherited even if false is passed in for inherit; this only affects the default behavior for inheritance.

    Returns [boolean, number]

    true if the property was found in the properties for this theme node (or in the properties of parent nodes when inheriting.)

  • Generically looks up a property containing a single length value. When specific getters (like st_theme_node_get_border_width()) exist, they should be used instead. They are cached, so more efficient, and have handling for shortcut properties and other details of CSS.

    See also st_theme_node_get_length(), which provides a simpler API.

    Parameters

    • property_name: string

      The name of the length property

    • inherit: boolean

      if true, if a value is not found for the property on the node, then it will be looked up on the parent node, and then on the parent's parent, and so forth. Note that if the property has a value of 'inherit' it will be inherited even if false is passed in for inherit; this only affects the default behavior for inheritance.

    Returns [boolean, number]

    true if the property was found in the properties for this theme node (or in the properties of parent nodes when inheriting.)

  • If the property is not found, the value in the shadow variable will not be changed.

    Generically looks up a property containing a set of shadow values. When specific getters (like st_theme_node_get_box_shadow ()) exist, they should be used instead. They are cached, so more efficient, and have handling for shortcut properties and other details of CSS.

    See also st_theme_node_get_shadow(), which provides a simpler API.

    Parameters

    • property_name: string

      The name of the shadow property

    • inherit: boolean

      if true, if a value is not found for the property on the node, then it will be looked up on the parent node, and then on the parent's parent, and so forth. Note that if the property has a value of 'inherit' it will be inherited even if false is passed in for inherit; this only affects the default behavior for inheritance.

    Returns [boolean, St.Shadow]

    true if the property was found in the properties for this theme node (or in the properties of parent nodes when inheriting.), false if the property was not found, or was explicitly set to 'none'.

  • Generically looks up a property containing a single time value, which is converted to milliseconds.

    Parameters

    • property_name: string

      The name of the time property

    • inherit: boolean

      if true, if a value is not found for the property on the node, then it will be looked up on the parent node, and then on the parent's parent, and so forth. Note that if the property has a value of 'inherit' it will be inherited even if false is passed in for inherit; this only affects the default behavior for inheritance.

    Returns [boolean, number]

    true if the property was found in the properties for this theme node (or in the properties of parent nodes when inheriting.)

  • Looks up a property containing a single URL value.

    See also st_theme_node_get_url(), which provides a simpler API.

    Parameters

    • property_name: string

      The name of the string property

    • inherit: boolean

      if true, if a value is not found for the property on the node, then it will be looked up on the parent node, and then on the parent's parent, and so forth. Note that if the property has a value of 'inherit' it will be inherited even if false is passed in for inherit; this only affects the default behavior for inheritance.

    Returns [boolean, Gio.File]

    true if the property was found in the properties for this theme node (or in the properties of parent nodes when inheriting.)

  • Check if st_theme_node_paint() will paint identically for node as it does for other. Note that in some cases this function may return true even if there is no visible difference in the painting.

    Parameters

    Returns boolean

    true if the two theme nodes paint identically. false if the two nodes potentially paint differently.

  • Serialize node to a string of its GObject.GType name, CSS ID, classes and pseudo-classes.

    Returns string

    the serialized theme node

Methods - Inherited from GObject

  • Creates a binding between source_property on source and target_property on target.

    Whenever the source_property is changed the target_property is updated using the same value. For instance:

      g_object_bind_property (action, "active", widget, "sensitive", 0);
    

    Will result in the "sensitive" property of the widget GObject.Object instance to be updated with the same value of the "active" property of the action GObject.Object instance.

    If flags contains GObject.BindingFlags.BIDIRECTIONAL then the binding will be mutual: if target_property on target changes then the source_property on source will be updated as well.

    The binding will automatically be removed when either the source or the target instances are finalized. To remove the binding without affecting the source and the target you can just call g_object_unref() on the returned GObject.Binding instance.

    Removing the binding by calling g_object_unref() on it must only be done if the binding, source and target are only used from a single thread and it is clear that both source and target outlive the binding. Especially it is not safe to rely on this if the binding, source or target can be finalized from different threads. Keep another reference to the binding and use g_binding_unbind() instead to be on the safe side.

    A GObject.Object can have multiple bindings.

    Parameters

    Returns GObject.Binding

    the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.

  • Disconnects a handler from an instance so it will not be called during any future or currently ongoing emissions of the signal it has been connected to.

    Parameters

    • id: number

      Handler ID of the handler to be disconnected

    Returns void

  • This function is intended for GObject.Object implementations to re-enforce a [floating][floating-ref] object reference. Doing this is seldom required: all GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().

    Returns void

  • Increases the freeze count on object. If the freeze count is non-zero, the emission of "notify" signals on object is stopped. The signals are queued until the freeze count is decreased to zero. Duplicate notifications are squashed so that at most one GObject.Object::notify signal is emitted for each property modified while the object is frozen.

    This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.

    Returns void

  • Gets a named field from the objects table of associations (see g_object_set_data()).

    Parameters

    • key: string

      name of the key for that association

    Returns any

    the data if found, or null if no such data exists.

  • Gets a property of an object.

    The value can be:

    • an empty GObject.Value initialized by G_VALUE_INIT, which will be automatically initialized with the expected type of the property (since GLib 2.60)
    • a GObject.Value initialized with the expected type of the property
    • a GObject.Value initialized with a type to which the expected type of the property can be transformed

    In general, a copy is made of the property contents and the caller is responsible for freeing the memory by calling GObject.Value.unset.

    Note that GObject.Object.get_property is really intended for language bindings, GObject.Object.get is much more convenient for C programming.

    Parameters

    • property_name: string

      The name of the property to get

    • value: any

      Return location for the property value. Can be an empty GObject.Value initialized by G_VALUE_INIT (auto-initialized with expected type since GLib 2.60), a GObject.Value initialized with the expected property type, or a GObject.Value initialized with a transformable type

    Returns any

  • This function gets back user data pointers stored via g_object_set_qdata().

    Parameters

    • quark: number

      A GLib.Quark, naming the user data pointer

    Returns any

    The user data pointer set, or null

  • Gets n_properties properties for an object. Obtained properties will be set to values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.

    Parameters

    • names: string[]

      the names of each property to get

    • values: any[]

      the values of each property to get

    Returns void

  • Emits a "notify" signal for the property property_name on object.

    When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

    Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.

    Parameters

    • property_name: string

      the name of a property installed on the class of object.

    Returns void

  • Emits a "notify" signal for the property specified by pspec on object.

    This function omits the property name lookup, hence it is faster than g_object_notify().

    One way to avoid using g_object_notify() from within the class that registered the properties, and using g_object_notify_by_pspec() instead, is to store the GParamSpec used with g_object_class_install_property() inside a static array, e.g.:

      typedef enum
    {
    PROP_FOO = 1,
    PROP_LAST
    } MyObjectProperty;

    static GParamSpec *properties[PROP_LAST];

    static void
    my_object_class_init (MyObjectClass *klass)
    {
    properties[PROP_FOO] = g_param_spec_int ("foo", NULL, NULL,
    0, 100,
    50,
    G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
    g_object_class_install_property (gobject_class,
    PROP_FOO,
    properties[PROP_FOO]);
    }

    and then notify a change on the "foo" property with:

      g_object_notify_by_pspec (self, properties[PROP_FOO]);
    

    Parameters

    Returns void

  • Increases the reference count of object.

    Since GLib 2.56, if GLIB_VERSION_MAX_ALLOWED is 2.56 or greater, the type of object will be propagated to the return type (using the GCC typeof() extension), so any casting the caller needs to do on the return type must be explicit.

    Returns GObject.Object

    the same object

  • Increase the reference count of object, and possibly remove the [floating][floating-ref] reference, if object has a floating reference.

    In other words, if the object is floating, then this call "assumes ownership" of the floating reference, converting it to a normal reference by clearing the floating flag while leaving the reference count unchanged. If the object is not floating, then this call adds a new normal reference increasing the reference count by one.

    Since GLib 2.56, the type of object will be propagated to the return type under the same conditions as for g_object_ref().

    Returns GObject.Object

    object

  • Releases all references to other objects. This can be used to break reference cycles.

    This function should only be called from object system implementations.

    Returns void

  • Sets multiple properties of an object at once. The properties argument should be a dictionary mapping property names to values.

    Parameters

    • properties: { [key: string]: any }

      Object containing the properties to set

    Returns void

  • Each object carries around a table of associations from strings to pointers. This function lets you set an association.

    If the object already had an association with that name, the old association will be destroyed.

    Internally, the key is converted to a GLib.Quark using g_quark_from_string(). This means a copy of key is kept permanently (even after object has been finalized) — so it is recommended to only use a small, bounded set of values for key in your program, to avoid the GLib.Quark storage growing unbounded.

    Parameters

    • key: string

      name of the key

    • data: any

      data to associate with that key

    Returns void

  • Sets a property on an object.

    Parameters

    • property_name: string

      The name of the property to set

    • value: any

      The value to set the property to

    Returns void

  • Remove a specified datum from the object's data associations, without invoking the association's destroy handler.

    Parameters

    • key: string

      name of the key

    Returns any

    the data if found, or null if no such data exists.

  • This function gets back user data pointers stored via g_object_set_qdata() and removes the data from object without invoking its destroy() function (if any was set). Usually, calling this function is only required to update user data pointers with a destroy notifier, for example:

    void
    object_add_to_user_list (GObject *object,
    const gchar *new_string)
    {
    // the quark, naming the object data
    GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
    // retrieve the old string list
    GList *list = g_object_steal_qdata (object, quark_string_list);

    // prepend new string
    list = g_list_prepend (list, g_strdup (new_string));
    // this changed 'list', so we need to set it again
    g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
    }
    static void
    free_string_list (gpointer data)
    {
    GList *node, *list = data;

    for (node = list; node; node = node->next)
    g_free (node->data);
    g_list_free (list);
    }

    Using g_object_get_qdata() in the above example, instead of g_object_steal_qdata() would have left the destroy function set, and thus the partial string list would have been freed upon g_object_set_qdata_full().

    Parameters

    • quark: number

      A GLib.Quark, naming the user data pointer

    Returns any

    The user data pointer set, or null

  • Stops a signal's emission by the given signal name. This will prevent the default handler and any subsequent signal handlers from being invoked.

    Parameters

    • detailedName: string

      Name of the signal to stop emission of

    Returns void

  • Reverts the effect of a previous call to g_object_freeze_notify(). The freeze count is decreased on object and when it reaches zero, queued "notify" signals are emitted.

    Duplicate notifications for each property are squashed so that at most one GObject.Object::notify signal is emitted for each property, in the reverse order in which they have been queued.

    It is an error to call this function when the freeze count is zero.

    Returns void

  • Decreases the reference count of object. When its reference count drops to 0, the object is finalized (i.e. its memory is freed).

    If the pointer to the GObject.Object may be reused in future (for example, if it is an instance variable of another object), it is recommended to clear the pointer to null rather than retain a dangling pointer to a potentially invalid GObject.Object instance. Use g_clear_object() for this.

    Returns void

  • the constructed function is called by g_object_new() as the final step of the object creation process. At the point of the call, all construction properties have been set on the object. The purpose of this call is to allow for object initialisation steps that can only be performed after construction properties have been set. constructed implementors should chain up to the constructed call of their parent class to allow it to complete its initialisation.

    Returns void

  • the dispose function is supposed to drop all references to other objects, but keep the instance otherwise intact, so that client method invocations still work. It may be run multiple times (due to reference loops). Before returning, dispose should chain up to the dispose method of the parent class.

    Returns void

  • instance finalization function, should finish the finalization of the instance begun in dispose and chain up to the finalize method of the parent class.

    Returns void

  • Emits a "notify" signal for the property property_name on object.

    When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

    Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.

    Parameters

    Returns void

  • the generic setter for all properties of this type. Should be overridden for every type with properties. If implementations of set_property don't emit property change notification explicitly, this will be done implicitly by the type system. However, if the notify signal is emitted explicitly, the type system will not emit it a second time.

    Parameters

    Returns void

  • This function essentially limits the life time of the closure to the life time of the object. That is, when the object is finalized, the closure is invalidated by calling g_closure_invalidate() on it, in order to prevent invocations of the closure with a finalized (nonexisting) object. Also, g_object_ref() and g_object_unref() are added as marshal guards to the closure, to ensure that an extra reference count is held on object during invocation of the closure. Usually, this function will be called on closures that use this object as closure data.

    Parameters

    Returns void

  • Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created GObject.ParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.

    This function is meant to be called from the interface's default vtable initialization function (the class_init member of GObject.TypeInfo.) It must not be called after after class_init has been called for any object types implementing this interface.

    If pspec is a floating reference, it will be consumed.

    Parameters

    Returns void

  • Parameters

    • property_id: number

      the new property ID

    • name: string

      the name of a property registered in a parent class or in an interface of this class.

    Returns void

Interfaces

ConstructorProps
SignalSignatures