gobject/org.gtkkn.bindings.gobject/Binding

Binding

open class Binding(pointer: <Error class: unknown class><<Error class: unknown class>>) : Object, KGTyped

GObject instance (or source) and another property on another GObject instance (or target).

Whenever the source property changes, the same value is applied to the target property; for instance, the following binding:

g_object_bind_property (object1, "property-a",
                        object2, "property-b",
                        G_BINDING_DEFAULT);

will cause the property named "property-b" of @object2 to be updated every time method@GObject.set or the specific accessor changes the value of the property "property-a" of @object1.

It is possible to create a bidirectional binding between two properties of two GObject instances, so that if either property changes, the other is updated as well, for instance:

g_object_bind_property (object1, "property-a",
                        object2, "property-b",
                        G_BINDING_BIDIRECTIONAL);

will keep the two properties in sync.

It is also possible to set a custom transformation function (in both directions, in case of a bidirectional binding) to apply a custom transformation from the source value to the target value before applying it; for instance, the following binding:

g_object_bind_property_full (adjustment1, "value",
                             adjustment2, "value",
                             G_BINDING_BIDIRECTIONAL,
                             celsius_to_fahrenheit,
                             fahrenheit_to_celsius,
                             NULL, NULL);

will keep the "value" property of the two adjustments in sync; the

Since

2.26

Constructors

Binding

constructor(pointer: <Error class: unknown class><<Error class: unknown class>>)

Types

Companion

object Companion : TypeCompanion<Binding>

Properties

flags

open val flags: BindingFlags

Flags to be used to control the #GBinding

gobjectBindingPointer

val gobjectBindingPointer: <Error class: unknown class><<Error class: unknown class>>

gPointer

val gPointer: <Error class: unknown class><GObject>

source

open val source: Object?

The #GObject that should be used as the source of the binding

sourceProperty

open val sourceProperty: String

The name of the property of #GBinding:source that should be used as the source of the binding.

target

open val target: Object?

The #GObject that should be used as the target of the binding

targetProperty

open val targetProperty: String

The name of the property of #GBinding:target that should be used as the target of the binding.

Functions

addToggleRef

open fun addToggleRef(notify: ToggleNotify)

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.

asType

inline fun <T : KGTyped> Object.asType(): T

Convert object into type T.

bindProperty

open fun bindProperty(sourceProperty: String, target: Object, targetProperty: String, flags: BindingFlags): Binding

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

bindPropertyFull

open fun bindPropertyFull(sourceProperty: String, target: Object, targetProperty: String, flags: BindingFlags, transformTo: Closure, transformFrom: Closure): Binding

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.

connectNotify

fun connectNotify(connectFlags: ConnectFlags = ConnectFlags(0u), handler: (pspec: ParamSpec) -> Unit): <Error class: unknown class>

The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.

dupData

open fun dupData(key: String, dupFunc: <Error class: unknown class>?): <Error class: unknown class>?

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

open fun dupQdata(quark: <Error class: unknown class>, dupFunc: <Error class: unknown class>?): <Error class: unknown class>?

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.

dupSource

open fun dupSource(): Object?

Retrieves the #GObject instance used as the source of the binding.

dupTarget

open fun dupTarget(): Object?

Retrieves the #GObject instance used as the target of the binding.

forceFloating

open fun forceFloating()

This function is intended for #GObject implementations to re-enforce a 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

open fun 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.

getBooleanProperty

fun Object.getBooleanProperty(propertyName: String): Boolean

getData

open fun getData(key: String): <Error class: unknown class>?

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

getIntProperty

fun Object.getIntProperty(propertyName: String): Int

getProperty

open fun getProperty(propertyName: String, value: Value)

Gets a property of an object.

getQdata

open fun getQdata(quark: <Error class: unknown class>): <Error class: unknown class>?

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

getStringProperty

fun Object.getStringProperty(propertyName: String): String?

isFloating

open fun isFloating(): Boolean

Checks whether @object has a floating-ref reference.

notify

open fun notify(propertyName: String)

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

notifyByPspec

open fun notifyByPspec(pspec: ParamSpec)

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

ref

open fun ref(): Object

Increases the reference count of @object.

refSink

open fun refSink(): Object

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

removeToggleRef

open fun removeToggleRef(notify: ToggleNotify)

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

runDispose

open fun runDispose()

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

setData

open fun setData(key: String, data: <Error class: unknown class>? = null)

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

setProperty

open fun setProperty(propertyName: String, value: Value)

Sets a property on an object.

setProperty

fun Object.setProperty(propertyName: String, value: Boolean)

fun Object.setProperty(propertyName: String, value: Int)

fun Object.setProperty(propertyName: String, value: String?)

setQdata

open fun setQdata(quark: <Error class: unknown class>, data: <Error class: unknown class>? = null)

This sets an opaque, named pointer on an object. The name is specified through a #GQuark (retrieved 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.

stealData

open fun stealData(key: String): <Error class: unknown class>?

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

stealQdata

open fun stealQdata(quark: <Error class: unknown class>): <Error class: unknown class>?

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);

takeRef

open fun takeRef(): Object

If @object is floating, sink it. Otherwise, do nothing.

thawNotify

open fun 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.

unbind

open fun unbind()

Explicitly releases the binding between the source and the target property expressed by @binding.

unref

open fun 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

open fun 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

weakRef

open fun weakRef(notify: WeakNotify)

Adds a weak reference callback to an object. Weak references are used for notification when an object is disposed. 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

open fun weakUnref(notify: WeakNotify)

Removes a weak reference callback to an object.