A class that is used to declare an event, which a number of listeners can subscribe to. More...

#include <app.hpp>

Public Types
using	event_args_type = TEventArgs

using	delegate_type = Delegate<void, const void*, TEventArgs>

using	function_type = typename delegate_type::function_type

using	event_token_type = typename delegate_type::token_type

Public Member Functions
constexpr	Event ()=default
	Initializes a new event.

constexpr	Event (const Event &_other)
	Creates a copy of a event.

constexpr	Event (Event &&_other) noexcept=default
	Takes over another instance of a event.

constexpr Event &	operator= (const Event &_other)
	Assigns a event by copying it.

constexpr Event &	operator= (Event &&_other) noexcept=default
	Assigns a event by taking it over.

constexpr	~Event () noexcept=default
	Releases the event instance.

event_token_type	add (const function_type &subscriber)
	Subscribes an event handler to the event.

bool	remove (const delegate_type &subscriber) noexcept
	Unsubscribes an event handler from the event.

bool	remove (event_token_type token) noexcept
	Unsubscribes an event handler from the event.

void	clear () noexcept
	Clears the event handlers.

void	invoke (const void *sender, const TEventArgs &args) const
	Invokes all event handlers of the event.

bool	contains (event_token_type token) const noexcept
	Returns `true`, if the event contains a subscriber with the provided token .

const delegate_type &	handler (event_token_type token) const
	Returns the delegate associated with token .

	operator bool () const noexcept
	Returns `true`, if any event handler is attached to the event, `false` otherwise.

event_token_type	operator+= (const function_type &subscriber)
	Subscribes an event handler to the event.

bool	operator-= (const delegate_type &subscriber) noexcept
	Unsubscribes an event handler from the event.

bool	operator-= (event_token_type token) noexcept
	Unsubscribes an event handler from the event.

void	operator() (const void *sender, const TEventArgs &args) const
	Invokes all event handlers of the event.

const delegate_type &	operator[] (event_token_type token) const
	Returns the delegate associated with token .

Detailed Description

template<typename TEventArgs>
class LiteFX::Event< TEventArgs >

A class that is used to declare an event, which a number of listeners can subscribe to.

A listener that subscribes to the event is called event handler. The event handler needs to be invokable and identifiable. Because of this, a Delegate is created for the event handler. A delegate stores the event handler, as well as a token to identify the event handler. Event handlers must expose the a common signature: they do not return anything and accept two parameters. The first parameter is an unformatted pointer to the event sender (i.e., the object that invoked the event handlers). The second parameter contains additional arguments (TEventArgs ), that are passed to all handlers. Note that the sender can also be nullptr.

Template Parameters

TEventArgs The type of the additional event arguments.

See also: EventArgs

Member Typedef Documentation

◆ delegate_type

template<typename TEventArgs >

using LiteFX::Event< TEventArgs >::delegate_type = Delegate<void, const void*, TEventArgs>

◆ event_args_type

template<typename TEventArgs >

using LiteFX::Event< TEventArgs >::event_args_type = TEventArgs

◆ event_token_type

template<typename TEventArgs >

using LiteFX::Event< TEventArgs >::event_token_type = typename delegate_type::token_type

◆ function_type

template<typename TEventArgs >

using LiteFX::Event< TEventArgs >::function_type = typename delegate_type::function_type

Constructor & Destructor Documentation

◆ Event() [1/3]

template<typename TEventArgs >

LiteFX::Event< TEventArgs >::Event ( )

constexprdefault

Initializes a new event.

◆ Event() [2/3]

template<typename TEventArgs >

LiteFX::Event< TEventArgs >::Event ( const Event< TEventArgs > & _other )

inlineconstexpr

Creates a copy of a event.

This constructor is implemented in order to support copying of types that contain events. Subscribers are not copied!

Parameters

_other The event instance to copy.

◆ Event() [3/3]

template<typename TEventArgs >

LiteFX::Event< TEventArgs >::Event ( Event< TEventArgs > && _other )

constexprdefaultnoexcept

Takes over another instance of a event.

Parameters

_other The event instance to take over.

◆ ~Event()

template<typename TEventArgs >

LiteFX::Event< TEventArgs >::~Event ( )

constexprdefaultnoexcept

Releases the event instance.

Member Function Documentation

◆ add()

template<typename TEventArgs >

event_token_type LiteFX::Event< TEventArgs >::add ( const function_type & subscriber )

inline

Subscribes an event handler to the event.

Parameters

subscriber A delegate for the event handler.

Returns: A unique token of the event handler.

◆ clear()

template<typename TEventArgs >

void LiteFX::Event< TEventArgs >::clear ( )

inlinenoexcept

Clears the event handlers.

◆ contains()

template<typename TEventArgs >

bool LiteFX::Event< TEventArgs >::contains ( event_token_type token ) const

inlinenoexcept

Returns true, if the event contains a subscriber with the provided token .

Parameters

token The token of an event.

Returns: true, if the event contains a subscriber with the provided token , false otherwise.

◆ handler()

template<typename TEventArgs >

const delegate_type & LiteFX::Event< TEventArgs >::handler ( event_token_type token ) const

inline

Returns the delegate associated with token .

Parameters

token The token to query for.

Returns: A reference of the delegate associated with token .

Exceptions

InvalidArgumentException Thrown, if the event does not have a subscriber with the provided token.

◆ invoke()

template<typename TEventArgs >

void LiteFX::Event< TEventArgs >::invoke	(	const void *	sender,
		const TEventArgs &	args ) const

inline

Invokes all event handlers of the event.

Parameters

sender	The source of the event.
args	The additional event arguments.

◆ operator bool()

template<typename TEventArgs >

LiteFX::Event< TEventArgs >::operator bool ( ) const

inlineexplicitnoexcept

Returns true, if any event handler is attached to the event, false otherwise.

Returns: true, if any event handler is attached to the event, false otherwise.

◆ operator()()

template<typename TEventArgs >

void LiteFX::Event< TEventArgs >::operator()	(	const void *	sender,
		const TEventArgs &	args ) const

inline

Invokes all event handlers of the event.

Parameters

sender	The source of the event.
args	The additional event arguments.

◆ operator+=()

template<typename TEventArgs >

event_token_type LiteFX::Event< TEventArgs >::operator+= ( const function_type & subscriber )

inline

Subscribes an event handler to the event.

Parameters

subscriber A delegate for the event handler.

Returns: A unique token of the event handler.

◆ operator-=() [1/2]

template<typename TEventArgs >

bool LiteFX::Event< TEventArgs >::operator-= ( const delegate_type & subscriber )

inlinenoexcept

Unsubscribes an event handler from the event.

Parameters

subscriber A delegate for the event handler.

Returns: true, if the event handler has been removed, false otherwise.

◆ operator-=() [2/2]

template<typename TEventArgs >

bool LiteFX::Event< TEventArgs >::operator-= ( event_token_type token )

inlinenoexcept

Unsubscribes an event handler from the event.

Parameters

toke	The unique token of the event handler.

Returns: true, if the event handler has been removed, false otherwise.

◆ operator=() [1/2]

template<typename TEventArgs >

Event & LiteFX::Event< TEventArgs >::operator= ( const Event< TEventArgs > & _other )

inlineconstexpr

Assigns a event by copying it.

This operator is implemented in order to support copying of types that contain events. Subscribers are not copied and previous subscriptions are cleared!

Parameters

_other The event instance to copy.

Returns: A reference to the current event instance.

◆ operator=() [2/2]

template<typename TEventArgs >

Event & LiteFX::Event< TEventArgs >::operator= ( Event< TEventArgs > && _other )

constexprdefaultnoexcept

Assigns a event by taking it over.

Parameters

_other The event to take over.

Returns: A reference to the current event instance.

◆ operator[]()

template<typename TEventArgs >

const delegate_type & LiteFX::Event< TEventArgs >::operator[] ( event_token_type token ) const

inline

Returns the delegate associated with token .

Parameters

token The token to query for.

Returns: A reference of the delegate associated with token .

Exceptions

InvalidArgumentException Thrown, if the event does not have a subscriber with the provided token.

◆ remove() [1/2]

template<typename TEventArgs >

bool LiteFX::Event< TEventArgs >::remove ( const delegate_type & subscriber )

inlinenoexcept

Unsubscribes an event handler from the event.

Parameters

subscriber A delegate for the event handler.

Returns: true, if the event handler has been removed, false otherwise.

◆ remove() [2/2]

template<typename TEventArgs >

bool LiteFX::Event< TEventArgs >::remove ( event_token_type token )

inlinenoexcept

Unsubscribes an event handler from the event.

Parameters

toke	The unique token of the event handler.

Returns: true, if the event handler has been removed, false otherwise.

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ delegate_type

◆ event_args_type

◆ event_token_type

◆ function_type

Constructor & Destructor Documentation

◆ Event() [1/3]

◆ Event() [2/3]

◆ Event() [3/3]

◆ ~Event()

Member Function Documentation

◆ add()

◆ clear()

◆ contains()

◆ handler()

◆ invoke()

◆ operator bool()

◆ operator()()

◆ operator+=()

◆ operator-=() [1/2]

◆ operator-=() [2/2]

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ operator[]()

◆ remove() [1/2]

◆ remove() [2/2]