StyleContext

#GtkStyleContext is an object that stores styling information affecting a widget defined by #GtkWidgetPath.

In order to construct the final style information, #GtkStyleContext queries information from all attached #GtkStyleProviders. Style providers can be either attached explicitly to the context through gtk_style_context_add_provider(), or to the screen through gtk_style_context_add_provider_for_screen(). The resulting style is a combination of all providers’ information in priority order.

For GTK+ widgets, any #GtkStyleContext returned by gtk_widget_get_style_context() will already have a #GtkWidgetPath, a #GdkScreen and RTL/LTR information set. The style context will also be updated automatically if any of these settings change on the widget.

If you are using the theming layer standalone, you will need to set a widget path and a screen yourself to the created style context through gtk_style_context_set_path() and gtk_style_context_set_screen(), as well as updating the context yourself using gtk_style_context_invalidate() whenever any of the conditions change, such as a change in the #GtkSettings:gtk-theme-name setting or a hierarchy change in the rendered widget. See the “Foreign drawing“ example in gtk3-demo.

Style Classes # {#gtkstylecontext-classes}

Widgets can add style classes to their context, which can be used to associate different styles by class. The documentation for individual widgets lists which style classes it uses itself, and which style classes may be added by applications to affect their appearance.

GTK+ defines macros for a number of style classes.

Style Regions

Widgets can also add regions with flags to their context. This feature is deprecated and will be removed in a future GTK+ update. Please use style classes instead.

GTK+ defines macros for a number of style regions.

Custom styling in UI libraries and applications

If you are developing a library with custom #GtkWidgets that render differently than standard components, you may need to add a #GtkStyleProvider yourself with the %GTK_STYLE_PROVIDER_PRIORITY_FALLBACK priority, either a #GtkCssProvider or a custom object implementing the #GtkStyleProvider interface. This way themes may still attempt to style your UI elements in a different way if needed so.

If you are using custom styling on an applications, you probably want then to make your style information prevail to the theme’s, so you must use a #GtkStyleProvider with the %GTK_STYLE_PROVIDER_PRIORITY_APPLICATION priority, keep in mind that the user settings in XDG_CONFIG_HOME/gtk-3.0/gtk.css will still take precedence over your changes, as it uses the %GTK_STYLE_PROVIDER_PRIORITY_USER priority.

class StyleContext : ObjectG {}

Constructors

this
this(GtkStyleContext* gtkStyleContext, bool ownedRef)

Sets our main struct and passes it to the parent class.

this
this()

Creates a standalone #GtkStyleContext, this style context won’t be attached to any widget, so you may want to call gtk_style_context_set_path() yourself.

Members

Classes

OnChangedDelegateWrapper
class OnChangedDelegateWrapper
Undocumented in source.

Functions

addClass
void addClass(string className)

Adds a style class to @context, so posterior calls to gtk_style_context_get() or any of the gtk_render_*() functions will make use of this new class for styling.

addOnChanged
gulong addOnChanged(void delegate(StyleContext) dlg, ConnectFlags connectFlags)

The ::changed signal is emitted when there is a change in the #GtkStyleContext.

addProvider
void addProvider(StyleProviderIF provider, uint priority)

Adds a style provider to @context, to be used in style construction. Note that a style provider added by this function only affects the style of the widget to which @context belongs. If you want to affect the style of all widgets, use gtk_style_context_add_provider_for_screen().

addRegion
void addRegion(string regionName, GtkRegionFlags flags)

Adds a region to @context, so posterior calls to gtk_style_context_get() or any of the gtk_render_*() functions will make use of this new region for styling.

cancelAnimations
void cancelAnimations(void* regionId)

Stops all running animations for @region_id and all animatable regions underneath.

getBackgroundColor
void getBackgroundColor(GtkStateFlags state, RGBA color)

Gets the background color for a given state.

getBorder
void getBorder(GtkStateFlags state, Border border)

Gets the border for a given state as a #GtkBorder.

getBorderColor
void getBorderColor(GtkStateFlags state, RGBA color)

Gets the border color for a given state.

getColor
void getColor(GtkStateFlags state, RGBA color)

Gets the foreground color for a given state.

getDirection
GtkTextDirection getDirection()

Returns the widget direction used for rendering.

getFont
PgFontDescription getFont(GtkStateFlags state)

Returns the font description for a given state. The returned object is const and will remain valid until the #GtkStyleContext::changed signal happens.

getFrameClock
FrameClock getFrameClock()

Returns the #GdkFrameClock to which @context is attached.

getJunctionSides
GtkJunctionSides getJunctionSides()

Returns the sides where rendered elements connect visually with others.

getMargin
void getMargin(GtkStateFlags state, Border margin)

Gets the margin for a given state as a #GtkBorder. See gtk_style_property_get() and #GTK_STYLE_PROPERTY_MARGIN for details.

getPadding
void getPadding(GtkStateFlags state, Border padding)

Gets the padding for a given state as a #GtkBorder. See gtk_style_context_get() and #GTK_STYLE_PROPERTY_PADDING for details.

getParent
StyleContext getParent()

Gets the parent context set via gtk_style_context_set_parent(). See that function for details.

getPath
WidgetPath getPath()

Returns the widget path used for style matching.

getProperty
void getProperty(string property, GtkStateFlags state, Value value)

Gets a style property from @context for the given state.

getScale
int getScale()

Returns the scale used for assets.

getScreen
Screen getScreen()

Returns the #GdkScreen to which @context is attached.

getSection
CssSection getSection(string property)

Queries the location in the CSS where @property was defined for the current @context. Note that the state to be queried is taken from gtk_style_context_get_state().

getState
GtkStateFlags getState()

Returns the state used for style matching.

getStruct
void* getStruct()

the main Gtk struct as a void*

getStyleContextStruct
GtkStyleContext* getStyleContextStruct(bool transferOwnership)

Get the main Gtk struct

getStyleProperty
void getStyleProperty(string propertyName, Value value)

Gets the value for a widget style property.

getStyleValist
void getStyleValist(void* args)

Retrieves several widget style properties from @context according to the current style.

getValist
void getValist(GtkStateFlags state, void* args)

Retrieves several style property values from @context for a given state.

hasClass
bool hasClass(string className)

Returns %TRUE if @context currently has defined the given class name.

hasRegion
bool hasRegion(string regionName, GtkRegionFlags flagsReturn)

Returns %TRUE if @context has the region defined. If @flags_return is not %NULL, it is set to the flags affecting the region.

invalidate
void invalidate()

Invalidates @context style information, so it will be reconstructed again. It is useful if you modify the @context and need the new information immediately.

listClasses
ListG listClasses()

Returns the list of classes currently defined in @context.

listRegions
ListG listRegions()

Returns the list of regions currently defined in @context.

lookupColor
bool lookupColor(string colorName, RGBA color)

Looks up and resolves a color name in the @context color map.

lookupIconSet
IconSet lookupIconSet(string stockId)

Looks up @stock_id in the icon factories associated to @context and the default icon factory, returning an icon set if found, otherwise %NULL.

notifyStateChange
void notifyStateChange(Window window, void* regionId, GtkStateType state, bool stateValue)

Notifies a state change on @context, so if the current style makes use of transition animations, one will be started so all rendered elements under @region_id are animated for state @state being set to value @state_value.

popAnimatableRegion
void popAnimatableRegion()

Pops an animatable region from @context. See gtk_style_context_push_animatable_region().

pushAnimatableRegion
void pushAnimatableRegion(void* regionId)

Pushes an animatable region, so all further gtk_render_*() calls between this call and the following gtk_style_context_pop_animatable_region() will potentially show transition animations for this region if gtk_style_context_notify_state_change() is called for a given state, and the current theme/style defines transition animations for state changes.

removeClass
void removeClass(string className)

Removes @class_name from @context.

removeProvider
void removeProvider(StyleProviderIF provider)

Removes @provider from the style providers list in @context.

removeRegion
void removeRegion(string regionName)

Removes a region from @context.

restore
void restore()

Restores @context state to a previous stage. See gtk_style_context_save().

save
void save()

Saves the @context state, so temporary modifications done through gtk_style_context_add_class(), gtk_style_context_remove_class(), gtk_style_context_set_state(), etc. can quickly be reverted in one go through gtk_style_context_restore().

scrollAnimations
void scrollAnimations(Window window, int dx, int dy)

This function is analogous to gdk_window_scroll(), and should be called together with it so the invalidation areas for any ongoing animation are scrolled together with it.

setBackground
void setBackground(Window window)

Sets the background of @window to the background pattern or color specified in @context for its current state.

setDirection
void setDirection(GtkTextDirection direction)

Sets the reading direction for rendering purposes.

setFrameClock
void setFrameClock(FrameClock frameClock)

Attaches @context to the given frame clock.

setJunctionSides
void setJunctionSides(GtkJunctionSides sides)

Sets the sides where rendered elements (mostly through gtk_render_frame()) will visually connect with other visual elements.

setParent
void setParent(StyleContext parent)

Sets the parent style context for @context. The parent style context is used to implement inheritance

of properties.

setPath
void setPath(WidgetPath path)

Sets the #GtkWidgetPath used for style matching. As a consequence, the style will be regenerated to match the new given path.

setScale
void setScale(int scale)

Sets the scale to use when getting image assets for the style.

setScreen
void setScreen(Screen screen)

Attaches @context to the given screen.

setState
void setState(GtkStateFlags flags)

Sets the state to be used for style matching.

setStruct
void setStruct(GObject* obj)
Undocumented in source. Be warned that the author may not have intended to support it.
stateIsRunning
bool stateIsRunning(GtkStateType state, double progress)

Returns %TRUE if there is a transition animation running for the current region (see gtk_style_context_push_animatable_region()).

toString
string toString(GtkStyleContextPrintFlags flags)

Converts the style context into a string representation.

Static functions

addProviderForScreen
void addProviderForScreen(Screen screen, StyleProviderIF provider, uint priority)

Adds a global style provider to @screen, which will be used in style construction for all #GtkStyleContexts under @screen.

callBackChanged
void callBackChanged(GtkStyleContext* stylecontextStruct, OnChangedDelegateWrapper wrapper)
Undocumented in source. Be warned that the author may not have intended to support it.
callBackChangedDestroy
void callBackChangedDestroy(OnChangedDelegateWrapper wrapper, GClosure* closure)
Undocumented in source. Be warned that the author may not have intended to support it.
getType
GType getType()
removeProviderForScreen
void removeProviderForScreen(Screen screen, StyleProviderIF provider)

Removes @provider from the global style providers list in @screen.

renderActivity
void renderActivity(StyleContext context, Context cr, double x, double y, double width, double height)

Renders an activity indicator (such as in #GtkSpinner). The state %GTK_STATE_FLAG_CHECKED determines whether there is activity going on.

renderArrow
void renderArrow(StyleContext context, Context cr, double angle, double x, double y, double size)

Renders an arrow pointing to @angle.

renderBackground
void renderBackground(StyleContext context, Context cr, double x, double y, double width, double height)

Renders the background of an element.

renderBackgroundGetClip
void renderBackgroundGetClip(StyleContext context, double x, double y, double width, double height, GdkRectangle outClip)

Returns the area that will be affected (i.e. drawn to) when calling gtk_render_background() for the given @context and rectangle.

renderCheck
void renderCheck(StyleContext context, Context cr, double x, double y, double width, double height)

Renders a checkmark (as in a #GtkCheckButton).

renderExpander
void renderExpander(StyleContext context, Context cr, double x, double y, double width, double height)

Renders an expander (as used in #GtkTreeView and #GtkExpander) in the area defined by @x, @y, @width, @height. The state %GTK_STATE_FLAG_CHECKED determines whether the expander is collapsed or expanded.

renderExtension
void renderExtension(StyleContext context, Context cr, double x, double y, double width, double height, GtkPositionType gapSide)

Renders a extension (as in a #GtkNotebook tab) in the rectangle defined by @x, @y, @width, @height. The side where the extension connects to is defined by @gap_side.

renderFocus
void renderFocus(StyleContext context, Context cr, double x, double y, double width, double height)

Renders a focus indicator on the rectangle determined by @x, @y, @width, @height.

renderFrame
void renderFrame(StyleContext context, Context cr, double x, double y, double width, double height)

Renders a frame around the rectangle defined by @x, @y, @width, @height.

renderFrameGap
void renderFrameGap(StyleContext context, Context cr, double x, double y, double width, double height, GtkPositionType gapSide, double xy0Gap, double xy1Gap)

Renders a frame around the rectangle defined by (@x, @y, @width, @height), leaving a gap on one side. @xy0_gap and @xy1_gap will mean X coordinates for %GTK_POS_TOP and %GTK_POS_BOTTOM gap sides, and Y coordinates for %GTK_POS_LEFT and %GTK_POS_RIGHT.

renderHandle
void renderHandle(StyleContext context, Context cr, double x, double y, double width, double height)

Renders a handle (as in #GtkHandleBox, #GtkPaned and #GtkWindow’s resize grip), in the rectangle determined by @x, @y, @width, @height.

renderIcon
void renderIcon(StyleContext context, Context cr, Pixbuf pixbuf, double x, double y)

Renders the icon in @pixbuf at the specified @x and @y coordinates.

renderIconPixbuf
Pixbuf renderIconPixbuf(StyleContext context, IconSource source, GtkIconSize size)

Renders the icon specified by @source at the given @size, returning the result in a pixbuf.

renderIconSurface
void renderIconSurface(StyleContext context, Context cr, Surface surface, double x, double y)

Renders the icon in @surface at the specified @x and @y coordinates.

renderInsertionCursor
void renderInsertionCursor(StyleContext context, Context cr, double x, double y, PgLayout layout, int index, PangoDirection direction)

Draws a text caret on @cr at the specified index of @layout.

renderLayout
void renderLayout(StyleContext context, Context cr, double x, double y, PgLayout layout)

Renders @layout on the coordinates @x, @y

renderLine
void renderLine(StyleContext context, Context cr, double x0, double y0, double x1, double y1)

Renders a line from (x0, y0) to (x1, y1).

renderOption
void renderOption(StyleContext context, Context cr, double x, double y, double width, double height)

Renders an option mark (as in a #GtkRadioButton), the %GTK_STATE_FLAG_CHECKED state will determine whether the option is on or off, and %GTK_STATE_FLAG_INCONSISTENT whether it should be marked as undefined.

renderSlider
void renderSlider(StyleContext context, Context cr, double x, double y, double width, double height, GtkOrientation orientation)

Renders a slider (as in #GtkScale) in the rectangle defined by @x, @y, @width, @height. @orientation defines whether the slider is vertical or horizontal.

resetWidgets
void resetWidgets(Screen screen)

This function recomputes the styles for all widgets under a particular #GdkScreen. This is useful when some global parameter has changed that affects the appearance of all widgets, because when a widget gets a new style, it will both redraw and recompute any cached information about its appearance. As an example, it is used when the color scheme changes in the related #GtkSettings object.

Variables

gtkStyleContext
GtkStyleContext* gtkStyleContext;

the main Gtk struct

onChangedListeners
OnChangedDelegateWrapper[] onChangedListeners;
Undocumented in source.

Inherited Members

From ObjectG

gObject
GObject* gObject;

the main Gtk struct

ownedRef
bool ownedRef;
Undocumented in source.
getObjectGStruct
GObject* getObjectGStruct(bool transferOwnership)

Get the main Gtk struct

getStruct
void* getStruct()

the main Gtk struct as a void*

isGcRoot
bool isGcRoot;
Undocumented in source.
destroyNotify
void destroyNotify(ObjectG obj)
Undocumented in source. Be warned that the author may not have intended to support it.
toggleNotify
void toggleNotify(ObjectG obj, GObject* object, int isLastRef)
Undocumented in source. Be warned that the author may not have intended to support it.
~this
~this()
Undocumented in source.
getDObject
RT getDObject(U obj, bool ownedRef)

Gets a D Object from the objects table of associations.

setStruct
void setStruct(GObject* obj)
Undocumented in source. Be warned that the author may not have intended to support it.
setProperty
void setProperty(string propertyName, T value)
unref
deprecated void unref(ObjectG obj)
Undocumented in source. Be warned that the author may not have intended to support it.
doref
deprecated ObjectG doref(ObjectG obj)
Undocumented in source. Be warned that the author may not have intended to support it.
OnNotifyDelegateWrapper
class OnNotifyDelegateWrapper
Undocumented in source.
onNotifyListeners
OnNotifyDelegateWrapper[] onNotifyListeners;
Undocumented in source.
addOnNotify
gulong addOnNotify(void delegate(ParamSpec, ObjectG) dlg, string property, ConnectFlags connectFlags)

The notify signal is emitted on an object when one of its properties has been changed. Note that getting this signal doesn't guarantee that the value of the property has actually changed, it may also be emitted when the setter for the property is called to reinstate the previous value.

callBackNotify
void callBackNotify(GObject* objectgStruct, GParamSpec* pspec, OnNotifyDelegateWrapper wrapper)
Undocumented in source. Be warned that the author may not have intended to support it.
callBackNotifyDestroy
void callBackNotifyDestroy(OnNotifyDelegateWrapper wrapper, GClosure* closure)
Undocumented in source. Be warned that the author may not have intended to support it.
getType
GType getType()
compatControl
size_t compatControl(size_t what, void* data)
interfaceFindProperty
ParamSpec interfaceFindProperty(TypeInterface gIface, string propertyName)

Find the #GParamSpec with the given name for an interface. Generally, the interface vtable passed in as @g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().

interfaceInstallProperty
void interfaceInstallProperty(TypeInterface gIface, ParamSpec pspec)

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 #GParamSpec, 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.

interfaceListProperties
ParamSpec[] interfaceListProperties(TypeInterface gIface)

Lists the properties of an interface.Generally, the interface vtable passed in as @g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().

addToggleRef
void addToggleRef(GToggleNotify notify, void* data)

Increases the reference count of the object by one and sets a callback to be called when all other references to the object are dropped, or when this is already the last reference to the object and another reference is established.

addWeakPointer
void addWeakPointer(void* weakPointerLocation)

Adds a weak reference from weak_pointer to @object to indicate that the pointer located at @weak_pointer_location is only valid during the lifetime of @object. When the @object is finalized, @weak_pointer will be set to %NULL.

bindProperty
Binding bindProperty(string sourceProperty, ObjectG target, string targetProperty, GBindingFlags flags)

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:

bindPropertyFull
Binding bindPropertyFull(string sourceProperty, ObjectG target, string targetProperty, GBindingFlags flags, GBindingTransformFunc transformTo, GBindingTransformFunc transformFrom, void* userData, GDestroyNotify notify)

Complete version of g_object_bind_property().

bindPropertyWithClosures
Binding bindPropertyWithClosures(string sourceProperty, ObjectG target, string targetProperty, GBindingFlags flags, Closure transformTo, Closure transformFrom)

Creates a binding between @source_property on @source and @target_property on @target, allowing you to set the transformation functions to be used by the binding.

dupData
void* dupData(string key, GDuplicateFunc dupFunc, void* userData)

This is a variant of g_object_get_data() which returns a 'duplicate' of the value. @dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.

dupQdata
void* dupQdata(GQuark quark, GDuplicateFunc dupFunc, void* userData)

This is a variant of g_object_get_qdata() which returns a 'duplicate' of the value. @dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.

forceFloating
void forceFloating()

This function is intended for #GObject 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().

freezeNotify
void freezeNotify()

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::notify signal is emitted for each property modified while the object is frozen.

getData
void* getData(string key)

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

getProperty
void getProperty(string propertyName, Value value)

Gets a property of an object. @value must have been initialized to the expected type of the property (or a type to which the expected type can be transformed) using g_value_init().

getQdata
void* getQdata(GQuark quark)

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

getValist
void getValist(string firstPropertyName, void* varArgs)

Gets properties of an object.

getv
void getv(string[] names, Value[] values)

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.

isFloating
bool isFloating()

Checks whether @object has a floating[floating-ref] reference.

notify
void notify(string propertyName)

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

notifyByPspec
void notifyByPspec(ParamSpec pspec)

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

doref
ObjectG doref()

Increases the reference count of @object.

refSink
ObjectG refSink()

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

removeToggleRef
void removeToggleRef(GToggleNotify notify, void* data)

Removes a reference added with g_object_add_toggle_ref(). The reference count of the object is decreased by one.

removeWeakPointer
void removeWeakPointer(void* weakPointerLocation)

Removes a weak reference from @object that was previously added using g_object_add_weak_pointer(). The @weak_pointer_location has to match the one used with g_object_add_weak_pointer().

replaceData
bool replaceData(string key, void* oldval, void* newval, GDestroyNotify destroy, GDestroyNotify* oldDestroy)

Compares the user data for the key @key on @object with @oldval, and if they are the same, replaces @oldval with @newval.

replaceQdata
bool replaceQdata(GQuark quark, void* oldval, void* newval, GDestroyNotify destroy, GDestroyNotify* oldDestroy)

Compares the user data for the key @quark on @object with @oldval, and if they are the same, replaces @oldval with @newval.

runDispose
void runDispose()

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

setData
void setData(string key, void* data)

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

setDataFull
void setDataFull(string key, void* data, GDestroyNotify destroy)

Like g_object_set_data() except it adds notification for when the association is destroyed, either by setting it to a different value or when the object is destroyed.

setProperty
void setProperty(string propertyName, Value value)

Sets a property on an object.

setQdata
void setQdata(GQuark quark, void* data)

This sets an opaque, named pointer on an object. The name is specified through a #GQuark (retrived e.g. via g_quark_from_static_string()), and the pointer can be gotten back from the @object with g_object_get_qdata() until the @object is finalized. Setting a previously set user data pointer, overrides (frees) the old pointer set, using #NULL as pointer essentially removes the data stored.

setQdataFull
void setQdataFull(GQuark quark, void* data, GDestroyNotify destroy)

This function works like g_object_set_qdata(), but in addition, a void (*destroy) (gpointer) function may be specified which is called with @data as argument when the @object is finalized, or the data is being overwritten by a call to g_object_set_qdata() with the same @quark.

setValist
void setValist(string firstPropertyName, void* varArgs)

Sets properties on an object.

setv
void setv(string[] names, Value[] values)

Sets @n_properties properties for an @object. Properties to be set will be taken from @values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.

stealData
void* stealData(string key)

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

stealQdata
void* stealQdata(GQuark quark)

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: |[<!-- language="C" --> 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"); // retrive the old string list GList *list = g_object_steal_qdata (object, quark_string_list);

thawNotify
void thawNotify()

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.

unref
void unref()

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

watchClosure
void watchClosure(Closure closure)

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.

weakRef
void weakRef(GWeakNotify notify, void* data)

Adds a weak reference callback to an object. Weak references are used for notification when an object is finalized. They are called "weak references" because they allow you to safely hold a pointer to an object without calling g_object_ref() (g_object_ref() adds a strong reference, that is, forces the object to stay alive).

weakUnref
void weakUnref(GWeakNotify notify, void* data)

Removes a weak reference callback to an object.

clearObject
void clearObject(ObjectG objectPtr)

Clears a reference to a #GObject.

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