xentara::workbench::bindings::PropertyHandle Class Reference

A handle for accessing a property. More...

#include <xentara/workbench/bindings/PropertyHandle.hpp>

Public Member Functions
constexpr	PropertyHandle () noexcept=default
	Default constructor that constructs a null handle that does not reference a property.
constexpr	operator bool () const noexcept
	Checks whether the handle references a property.
template<PropertyChangedInvocable ChangeCallback>
auto	subscribe (ChangeCallback &&changeCallback) const -> PropertyController::Subscription
	Subscribes to the property.
auto	subscribe (PropertyController::SubscriptionCallbacks callbacks) const -> PropertyController::Subscription
	Subscribes to the property, with support for specialized callbacks.
auto	publish (Action action=Action::ValueChanged, std::size_t index={}) const -> void
	Publishes a value and state change for the property.
auto	publishValue (Action action=Action::ValueChanged, std::size_t index={}) const -> void
	Publishes a change to only the value of the property.
auto	publishState () const -> void
	Publishes a change in the state of the property.
auto	publishVisibility () const -> void
	Publishes a change in the visibility of the property.
auto	state () const -> const utils::eh::expected< void, ui::String > &
	Gets the state of the property.
auto	visible () const -> bool
	Gets the visibility of the property.
constexpr auto	controller () const noexcept -> PropertyController &
	Gets the controller.
constexpr auto	property () const noexcept -> const PropertyId &
	Gets the ID of the handled property.

Detailed Description

A handle for accessing a property.

This object allows publishing and subscribing to a property without needing access to the controller.

Constructor & Destructor Documentation

PropertyHandle()

constexpr xentara::workbench::bindings::PropertyHandle::PropertyHandle ( )

constexprdefaultnoexcept

Default constructor that constructs a null handle that does not reference a property.

Member Function Documentation

controller()

constexpr auto xentara::workbench::bindings::PropertyHandle::controller ( ) const -> PropertyController &

constexprnoexcept

Gets the controller.

Precondition

Must not be called on a null object

Returns

The controller

operator bool()

constexpr xentara::workbench::bindings::PropertyHandle::operator bool ( ) const

explicitconstexprnoexcept

Checks whether the handle references a property.

Returns

Return true if the handle is valid, or false if this is a ID that does not reference a property.

property()

constexpr auto xentara::workbench::bindings::PropertyHandle::property ( ) const -> const PropertyId &

constexprnoexcept

Gets the ID of the handled property.

Precondition

Must not be called on a null object

Returns

The property ID

publish()

auto xentara::workbench::bindings::PropertyHandle::publish	(	Action	action = Action::ValueChanged,
		std::size_t	index = {}
	)		const -> void

Publishes a value and state change for the property.

This function publishes both a value and a state change. To publish value and state changes separately, use publishValue() and publishState(), respectively. A visibility change is not published.

It is safe to call this function on a null handle. If the handle is null, the function will do nothing.

Parameters

action	The action that is being published
index	The index of the element that changed. This parameter is ignored if action is Action::ValueChanged.

publishState()

auto xentara::workbench::bindings::PropertyHandle::publishState

(

)

const -> void

Publishes a change in the state of the property.

publishValue()

auto xentara::workbench::bindings::PropertyHandle::publishValue	(	Action	action = Action::ValueChanged,
		std::size_t	index = {}
	)		const -> void

Publishes a change to only the value of the property.

Parameters

action	The action that is being published
index	The index of the element that changed. This parameter is ignored if action is Action::ValueChanged.

publishVisibility()

auto xentara::workbench::bindings::PropertyHandle::publishVisibility

(

)

const -> void

Publishes a change in the visibility of the property.

It is safe to call this function on a null handle. If the handle is null, the function will do nothing.

Note

A change in visibility may also result in an implicit change in state, since invisible properties cannot have an error state. If the change in visibility also results in a change of state, the state will be published as well.

state()

auto xentara::workbench::bindings::PropertyHandle::state

(

)

const -> const utils::eh::expected<void, ui::String> &

Gets the state of the property.

Returns

The current state of the property. The state will be either a short localized text describing the error, or a default constructed expected if there is no error.

Invisible properties cannot have error states. If the property is invisible, this function will always return a default constructed expected.

subscribe() [1/2]

template<PropertyChangedInvocable ChangeCallback>

auto xentara::workbench::bindings::PropertyHandle::subscribe

(

ChangeCallback &&

changeCallback

)

const -> PropertyController::Subscription

Subscribes to the property.

It is safe to call this function on a null handle. If the handle is null, the function will return a null subscription.

Parameters

changeCallback

A callback that will be called whenever the property’s value has changed.

Returns

An automatic object that can be used to unsubscribe the subscription.

subscribe() [2/2]

auto xentara::workbench::bindings::PropertyHandle::subscribe

(

PropertyController::SubscriptionCallbacks

callbacks

)

const -> PropertyController::Subscription

Subscribes to the property, with support for specialized callbacks.

It is safe to call this function on a null handle. If the handle is null, the function will do nothing.

Parameters

callbacks

The callbacks.

Returns

An automatic object that can be used to unsubscribe the subscription.

visible()

auto xentara::workbench::bindings::PropertyHandle::visible

(

)

const -> bool

Gets the visibility of the property.

Returns

Returns true if the property is visible, or false if it is hidden.