StWidget

## StWidget StWidget — Base class for stylable actors |

## Synopsis

    struct              StWidget;
    struct              StWidgetClass;
    char *              st_describe_actor                   (ClutterActor *actor);
    gfloat              st_get_slow_down_factor             (void);
    void                st_set_slow_down_factor             (gfloat factor);
    void                st_widget_add_accessible_state      (StWidget *widget,
                                                             AtkStateType state);
    void                st_widget_add_style_class_name      (StWidget *actor,
                                                             const gchar *style_class);
    void                st_widget_add_style_pseudo_class    (StWidget *actor,
                                                             const gchar *pseudo_class);
    void                st_widget_ensure_style              (StWidget *widget);
    const gchar *       st_widget_get_accessible_name       (StWidget *widget);
    AtkRole             st_widget_get_accessible_role       (StWidget *widget);
    gboolean            st_widget_get_can_focus             (StWidget *widget);
    GList *             st_widget_get_focus_chain           (StWidget *widget);
    gboolean            st_widget_get_hover                 (StWidget *widget);
    ClutterActor *      st_widget_get_label_actor           (StWidget *widget);
    const gchar *       st_widget_get_style                 (StWidget *actor);
    const gchar *       st_widget_get_style_class_name      (StWidget *actor);
    const gchar *       st_widget_get_style_pseudo_class    (StWidget *actor);
    StTheme *           st_widget_get_theme                 (StWidget *actor);
    StThemeNode *       st_widget_get_theme_node            (StWidget *widget);
    gboolean            st_widget_get_track_hover           (StWidget *widget);
    gboolean            st_widget_has_style_class_name      (StWidget *actor,
                                                             const gchar *style_class);
    gboolean            st_widget_has_style_pseudo_class    (StWidget *actor,
                                                             const gchar *pseudo_class);
    gboolean            st_widget_navigate_focus            (StWidget *widget,
                                                             ClutterActor *from,
                                                             GtkDirectionType direction,
                                                             gboolean wrap_around);
    void                st_widget_paint_background          (StWidget *widget);
    StThemeNode *       st_widget_peek_theme_node           (StWidget *widget);
    void                st_widget_remove_accessible_state   (StWidget *widget,
                                                             AtkStateType state);
    void                st_widget_remove_style_class_name   (StWidget *actor,
                                                             const gchar *style_class);
    void                st_widget_remove_style_pseudo_class (StWidget *actor,
                                                             const gchar *pseudo_class);
    void                st_widget_set_accessible_name       (StWidget *widget,
                                                             const gchar *name);
    void                st_widget_set_accessible_role       (StWidget *widget,
                                                             AtkRole role);
    void                st_widget_set_can_focus             (StWidget *widget,
                                                             gboolean can_focus);
    void                st_widget_set_hover                 (StWidget *widget,
                                                             gboolean hover);
    void                st_widget_set_label_actor           (StWidget *widget,
                                                             ClutterActor *label);
    void                st_widget_set_style                 (StWidget *actor,
                                                             const gchar *style);
    void                st_widget_set_style_class_name      (StWidget *actor,
                                                             const gchar *style_class_list);
    void                st_widget_set_style_pseudo_class    (StWidget *actor,
                                                             const gchar *pseudo_class_list);
    void                st_widget_set_theme                 (StWidget *actor,
                                                             StTheme *theme);
    void                st_widget_set_track_hover           (StWidget *widget,
                                                             gboolean track_hover);
    void                st_widget_style_changed             (StWidget *widget);
    void                st_widget_sync_hover                (StWidget *widget);

## Object Hierarchy

      GObject
       +----GInitiallyUnowned
             +----ClutterActor
                   +----StWidget
                         +----StBin
                         +----StBoxLayout
                         +----StDrawingArea
                         +----StEntry
                         +----StIcon
                         +----StLabel
                         +----StScrollBar
                         +----StTable

## Implemented Interfaces

StWidget implements ClutterContainer, ClutterScriptable, ClutterAnimatable and AtkImplementorIface.

## Properties

      "accessible-name"          gchar*                : Read / Write
      "accessible-role"          AtkRole               : Read / Write
      "can-focus"                gboolean              : Read / Write
      "hover"                    gboolean              : Read / Write
      "label-actor"              ClutterActor*         : Read / Write
      "pseudo-class"             gchar*                : Read / Write
      "stylable"                 gboolean              : Read / Write
      "style"                    gchar*                : Read / Write
      "style-class"              gchar*                : Read / Write
      "theme"                    StTheme*              : Read / Write
      "track-hover"              gboolean              : Read / Write

## Signals

      "popup-menu"                                     : Run Last
      "style-changed"                                  : Run Last

## Description

StWidget is a simple abstract class on top of ClutterActor. It provides basic themeing properties.

Actors in the St library should subclass StWidget if they plan to obey to a certain StStyle.

## Details

### struct StWidget

    struct StWidget;

Base class for stylable actors. The contents of the StWidget structure are private and should only be accessed through the public API.

### struct StWidgetClass

    struct StWidgetClass {
    };

Base class for stylable actors.

### st_describe_actor ()

    char *              st_describe_actor                   (ClutterActor *actor);

Creates a string describing `actor`, for use in debugging. This includes the class name and actor name (if any), plus if `actor` is an StWidget, its style class and pseudo class names.

`actor` : | a ClutterActor
Returns : | the debug name.

### st_get_slow_down_factor ()

    gfloat              st_get_slow_down_factor             (void);

Returns : | the global factor applied to all animation durations

### st_set_slow_down_factor ()

    void                st_set_slow_down_factor             (gfloat factor);

Set a global factor applied to all animation durations

`factor` : | new slow-down factor

### st_widget_add_accessible_state ()

    void                st_widget_add_accessible_state      (StWidget *widget,
                                                             AtkStateType state);

This method adds `state` as one of the accessible states for `widget`. The list of states of a widget describes the current state of user interface element `widget` and is provided so that assistive technologies know how to present `widget` to the user.

Usually you will have no need to add accessible states for an object, as the accessible object can extract most of the states from the object itself (ie: a StButton knows when it is pressed). This method is only required when one cannot extract the information automatically from the object itself (i.e.: a generic container used as a toggle menu item will not automatically include the toggled state).

`widget` : | A StWidget
`state` : | AtkStateType state to add

### st_widget_add_style_class_name ()

    void                st_widget_add_style_class_name      (StWidget *actor,
                                                             const gchar *style_class);

Adds `style_class` to `actor`'s style class name list, if it is not already present.

`actor` : | a StWidget
`style_class` : | a style class name string

### st_widget_add_style_pseudo_class ()

    void                st_widget_add_style_pseudo_class    (StWidget *actor,
                                                             const gchar *pseudo_class);

Adds `pseudo_class` to `actor`'s pseudo class list, if it is not already present.

`actor` : | a StWidget
`pseudo_class` : | a pseudo class string

### st_widget_ensure_style ()

    void                st_widget_ensure_style              (StWidget *widget);

Ensures that `widget` has read its style information.

`widget` : | A StWidget

### st_widget_get_accessible_name ()

    const gchar *       st_widget_get_accessible_name       (StWidget *widget);

Gets the accessible name for this widget. See `st_widget_set_accessible_name()` for more information.

`widget` : | widget to get the accessible name for
Returns : | a character string representing the accessible name of the widget.

### st_widget_get_accessible_role ()

    AtkRole             st_widget_get_accessible_role       (StWidget *widget);

Gets the AtkRole for this widget. See `st_widget_set_accessible_role()` for more information.

`widget` : | widget to get the accessible role for
Returns : | accessible AtkRole for this widget

### st_widget_get_can_focus ()

    gboolean            st_widget_get_can_focus             (StWidget *widget);

Returns the current value of the can-focus property. See `st_widget_set_can_focus()` for more information.

`widget` : | A StWidget
Returns : | current value of can-focus on `widget`

### st_widget_get_focus_chain ()

    GList *             st_widget_get_focus_chain           (StWidget *widget);

Gets a list of the focusable children of `widget`, in "Tab" order. By default, this returns all visible (as in `CLUTTER_ACTOR_IS_VISIBLE()`) children of `widget`.

`widget` : | An StWidget
Returns : | `widget`'s focusable children. [element-type Clutter.Actor][transfer container]

### st_widget_get_hover ()

    gboolean            st_widget_get_hover                 (StWidget *widget);

If "track-hover" is set, this returns whether the pointer is currently over the widget.

`widget` : | A StWidget
Returns : | current value of hover on `widget`

### st_widget_get_label_actor ()

    ClutterActor *      st_widget_get_label_actor           (StWidget *widget);

Gets the label that identifies `widget` if it is defined

`widget` : | a StWidget
Returns : | the label that identifies the widget. [transfer none]

### st_widget_get_style ()

    const gchar *       st_widget_get_style                 (StWidget *actor);

Get the current inline style string. See `st_widget_set_style()`.

`actor` : | a StWidget
Returns : | The inline style string, or `NULL`. The string is owned by the StWidget and should not be modified or freed.

### st_widget_get_style_class_name ()

    const gchar *       st_widget_get_style_class_name      (StWidget *actor);

Get the current style class name

`actor` : | a StWidget
Returns : | the class name string. The string is owned by the StWidget and should not be modified or freed.

### st_widget_get_style_pseudo_class ()

    const gchar *       st_widget_get_style_pseudo_class    (StWidget *actor);

Get the current style pseudo class list.

Note that an actor can have multiple pseudo classes; if you just want to test for the presence of a specific pseudo class, use `st_widget_has_style_pseudo_class()`.

`actor` : | a StWidget
Returns : | the pseudo class list string. The string is owned by the StWidget and should not be modified or freed.

### st_widget_get_theme ()

    StTheme *           st_widget_get_theme                 (StWidget *actor);

Gets the overriding theme set on the actor. See `st_widget_set_theme()`

`actor` : | a StWidget
Returns : | the overriding theme, or `NULL`. [transfer none]

### st_widget_get_theme_node ()

    StThemeNode *       st_widget_get_theme_node            (StWidget *widget);

Gets the theme node holding style information for the widget. The theme node is used to access standard and custom CSS properties of the widget.

Note: it is a fatal error to call this on a widget that is not been added to a stage.

`widget` : | a StWidget
Returns : | the theme node for the widget. This is owned by the widget. When attributes of the widget or the environment that affect the styling change (for example the style_class property of the widget), it will be recreated, and the ::style-changed signal will be emitted on the widget. [transfer none]

### st_widget_get_track_hover ()

    gboolean            st_widget_get_track_hover           (StWidget *widget);

Returns the current value of the track-hover property. See `st_widget_set_track_hover()` for more information.

`widget` : | A StWidget
Returns : | current value of track-hover on `widget`

### st_widget_has_style_class_name ()

    gboolean            st_widget_has_style_class_name      (StWidget *actor,
                                                             const gchar *style_class);

Tests if `actor`'s style class list includes `style_class`.

`actor` : | a StWidget
`style_class` : | a style class string
Returns : | whether or not `actor`'s style class list includes `style_class`.

### st_widget_has_style_pseudo_class ()

    gboolean            st_widget_has_style_pseudo_class    (StWidget *actor,
                                                             const gchar *pseudo_class);

Tests if `actor`'s pseudo class list includes `pseudo_class`.

`actor` : | a StWidget
`pseudo_class` : | a pseudo class string
Returns : | whether or not `actor`'s pseudo class list includes `pseudo_class`.

### st_widget_navigate_focus ()

    gboolean            st_widget_navigate_focus            (StWidget *widget,
                                                             ClutterActor *from,
                                                             GtkDirectionType direction,
                                                             gboolean wrap_around);

Tries to update the keyboard focus within `widget` in response to a keyboard event.

If `from` is a descendant of `widget`, this attempts to move the keyboard focus to the next descendant of `widget` (in the order implied by `direction`) that has the "can-focus" property set. If `from` is `NULL`, this attempts to focus either `widget` itself, or its first descendant in the order implied by `direction`. If `from` is outside of `widget`, it behaves as if it was a descendant if `direction` is one of the directional arrows and as if it was `NULL` otherwise.

If a container type is marked "can-focus", the expected behavior is that it will only take up a single slot on the focus chain as a whole, rather than allowing navigation between its child actors (or having a distinction between itself being focused and one of its children being focused).

Some widget classes might have slightly different behavior from the above, where that would make more sense.

If `wrap_around` is `TRUE` and `from` is a child of `widget`, but the widget has no further children that can accept the focus in the given direction, then `st_widget_navigate_focus()` will try a second time, using a `NULL` `from`, which should cause it to reset the focus to the first available widget in the given direction.

`widget` : | the "top level" container
`from` : | the actor that the focus is coming from. [allow-none]
`direction` : | the direction focus is moving in
`wrap_around` : | whether focus should wrap around
Returns : | `TRUE` if `clutter_actor_grab_key_focus()` has been called on an actor. `FALSE` if not.

### st_widget_paint_background ()

    void                st_widget_paint_background          (StWidget *widget);

Paint the background of the widget. This is meant to be called by subclasses of StWiget that need to paint the background without painting children.

`widget` : | The StWidget

### st_widget_peek_theme_node ()

    StThemeNode *       st_widget_peek_theme_node           (StWidget *widget);

Returns the theme node for the widget if it has already been computed, `NULL` if the widget hasn't been added to a stage or the theme node hasn't been computed. If `NULL` is returned, then ::style-changed will be reliably emitted before the widget is allocated or painted.

`widget` : | a StWidget
Returns : | the theme node for the widget. This is owned by the widget. When attributes of the widget or the environment that affect the styling change (for example the style_class property of the widget), it will be recreated, and the ::style-changed signal will be emitted on the widget. [transfer none]

### st_widget_remove_accessible_state ()

    void                st_widget_remove_accessible_state   (StWidget *widget,
                                                             AtkStateType state);

This method removes `state` as on of the accessible states for `widget`. See `st_widget_add_accessible_state()` for more information.

`widget` : | A StWidget
`state` : | AtkState state to remove

### st_widget_remove_style_class_name ()

    void                st_widget_remove_style_class_name   (StWidget *actor,
                                                             const gchar *style_class);

Removes `style_class` from `actor`'s style class name, if it is present.

`actor` : | a StWidget
`style_class` : | a style class name string

### st_widget_remove_style_pseudo_class ()

    void                st_widget_remove_style_pseudo_class (StWidget *actor,
                                                             const gchar *pseudo_class);

Removes `pseudo_class` from `actor`'s pseudo class, if it is present.

`actor` : | a StWidget
`pseudo_class` : | a pseudo class string

### st_widget_set_accessible_name ()

    void                st_widget_set_accessible_name       (StWidget *widget,
                                                             const gchar *name);

This method sets `name` as the accessible name for `widget`.

Usually you will have no need to set the accessible name for an object, as usually there is a label for most of the interface elements. So in general it is better to just use `st_widget_set_label_actor`. This method is only required when you need to set an accessible name and there is no available label object.

`widget` : | widget to set the accessible name for
`name` : | a character string to be set as the accessible name. [allow-none]

### st_widget_set_accessible_role ()

    void                st_widget_set_accessible_role       (StWidget *widget,
                                                             AtkRole role);

This method sets `role` as the accessible role for `widget`. This role describes what kind of user interface element `widget` is and is provided so that assistive technologies know how to present `widget` to the user.

Usually you will have no need to set the accessible role for an object, as this information is extracted from the context of the object (ie: a StButton has by default a push button role). This method is only required when you need to redefine the role currently associated with the widget, for instance if it is being used in an unusual way (ie: a StButton used as a togglebutton), or if a generic object is used directly (ie: a container as a menu item).

If `role` is ATK_ROLE_INVALID, the role will not be changed and the accessible's default role will be used instead.

`widget` : | widget to set the accessible role for
`role` : | The role to use

### st_widget_set_can_focus ()

    void                st_widget_set_can_focus             (StWidget *widget,
                                                             gboolean can_focus);

Marks `widget` as being able to receive keyboard focus via keyboard navigation.

`widget` : | A StWidget
`can_focus` : | `TRUE` if the widget can receive keyboard focus via keyboard navigation

### st_widget_set_hover ()

    void                st_widget_set_hover                 (StWidget *widget,
                                                             gboolean hover);

Sets `widget`'s hover property and adds or removes "hover" from its pseudo class accordingly.

If you have set "track-hover", you should not need to call this directly. You can call `st_widget_sync_hover()` if the hover state might be out of sync due to another actor's pointer grab.

`widget` : | A StWidget
`hover` : | whether the pointer is hovering over the widget

### st_widget_set_label_actor ()

    void                st_widget_set_label_actor           (StWidget *widget,
                                                             ClutterActor *label);

Sets `label` as the ClutterActor that identifies (labels) `widget`. `label` can be `NULL` to indicate that `widget` is not labelled any more

`widget` : | a StWidget
`label` : | a ClutterActor

### st_widget_set_style ()

    void                st_widget_set_style                 (StWidget *actor,
                                                             const gchar *style);

Set the inline style string for this widget. The inline style string is an optional ';'-separated list of CSS properties that override the style as determined from the stylesheets of the current theme.

`actor` : | a StWidget
`style` : | a inline style string, or `NULL`. [allow-none]

### st_widget_set_style_class_name ()

    void                st_widget_set_style_class_name      (StWidget *actor,
                                                             const gchar *style_class_list);

Set the style class name list. `style_class_list` can either be `NULL`, for no classes, or a space-separated list of style class names. See also `st_widget_add_style_class_name()` and `st_widget_remove_style_class_name()`.

`actor` : | a StWidget
`style_class_list` : | a new style class list string. [allow-none]

### st_widget_set_style_pseudo_class ()

    void                st_widget_set_style_pseudo_class    (StWidget *actor,
                                                             const gchar *pseudo_class_list);

Set the style pseudo class list. `pseudo_class_list` can either be `NULL`, for no classes, or a space-separated list of pseudo class names. See also `st_widget_add_style_pseudo_class()` and `st_widget_remove_style_pseudo_class()`.

`actor` : | a StWidget
`pseudo_class_list` : | a new pseudo class list string. [allow-none]

### st_widget_set_theme ()

    void                st_widget_set_theme                 (StWidget *actor,
                                                             StTheme *theme);

Overrides the theme that would be inherited from the actor's parent or the stage with an entirely new theme (set of stylesheets).

`actor` : | a StWidget
`theme` : | a new style class string

### st_widget_set_track_hover ()

    void                st_widget_set_track_hover           (StWidget *widget,
                                                             gboolean track_hover);

Enables hover tracking on the StWidget.

If hover tracking is enabled, and the widget is visible and reactive, then `widget`'s "hover" property will be updated automatically to reflect whether the pointer is in `widget` (or one of its children), and `widget`'s "pseudo-class" will have the "hover" class added and removed from it accordingly.

Note that currently it is not possible to correctly track the hover state when another actor has a pointer grab. You can use `st_widget_sync_hover()` to update the property manually in this case.

`widget` : | A StWidget
`track_hover` : | `TRUE` if the widget should track the pointer hover state

### st_widget_style_changed ()

    void                st_widget_style_changed             (StWidget *widget);

### st_widget_sync_hover ()

    void                st_widget_sync_hover                (StWidget *widget);

Sets `widget`'s hover state according to the current pointer position. This can be used to ensure that it is correct after (or during) a pointer grab.

`widget` : | A StWidget

## Property Details

### The `"accessible-name"` property

      "accessible-name"          gchar*                : Read / Write

Object instance's name for assistive technology access.

Default value: NULL

### The `"accessible-role"` property

      "accessible-role"          AtkRole               : Read / Write

The accessible role of this object

Default value: ATK_ROLE_INVALID

### The `"can-focus"` property

      "can-focus"                gboolean              : Read / Write

Whether or not the widget can be focused via keyboard navigation.

Default value: FALSE

### The `"hover"` property

      "hover"                    gboolean              : Read / Write

Whether or not the pointer is currently hovering over the widget. This is only tracked automatically if "track-hover" is `TRUE`, but you can adjust it manually in any case.

Default value: FALSE

### The `"label-actor"` property

      "label-actor"              ClutterActor*         : Read / Write

Label that identifies this widget.

### The `"pseudo-class"` property

      "pseudo-class"             gchar*                : Read / Write

The pseudo-class of the actor. Typical values include "hover", "active", "focus".

Default value: ""

### The `"stylable"` property

      "stylable"                 gboolean              : Read / Write

Enable or disable styling of the widget

Default value: TRUE

### The `"style"` property

      "style"                    gchar*                : Read / Write

Inline style information for the actor as a ';'-separated list of CSS properties.

Default value: ""

### The `"style-class"` property

      "style-class"              gchar*                : Read / Write

The style-class of the actor for use in styling.

Default value: ""

### The `"theme"` property

      "theme"                    StTheme*              : Read / Write

A theme set on this actor overriding the global theming for this actor and its descendants

### The `"track-hover"` property

      "track-hover"              gboolean              : Read / Write

Determines whether the widget tracks pointer hover state. If `TRUE` (and the widget is visible and reactive), the "hover" property and "hover" style pseudo class will be adjusted automatically as the pointer moves in and out of the widget.

Default value: FALSE

## Signal Details

### The `"popup-menu"` signal

    void                user_function                      (StWidget *widget,
                                                            gpointer  user_data)      : Run Last

Emitted when the user has requested a context menu (eg, via a keybinding)

`widget` : | the StWidget
`user_data` : | user data set when the signal handler was connected.

### The `"style-changed"` signal

    void                user_function                      (StWidget *widget,
                                                            gpointer  user_data)      : Run Last

Emitted when the style information that the widget derives from the theme changes

`widget` : | the StWidget
`user_data` : | user data set when the signal handler was connected.