ime::EventEmitter Class Reference

Class for creating and publishing events. More...

#include <EventEmitter.h>

Inheritance diagram for ime::EventEmitter:

Public Member Functions
	EventEmitter ()=default
	Default constructor. More...
	EventEmitter (const EventEmitter &)
	Copy constructor. More...
EventEmitter &	operator= (const EventEmitter &)
	Copy assignment operator. More...
	EventEmitter (EventEmitter &&) noexcept
	Move constructor. More...
EventEmitter &	operator= (EventEmitter &&) noexcept
	Move assignment operator. More...
template<typename... Args>
int	addEventListener (const std::string &event, Callback< Args... > callback)
	Add an event listener (callback) to an event. More...
template<typename... Args>
int	on (const std::string &event, Callback< Args... > callback)
	Add an event listener to an event. More...
template<typename ... Args>
int	addOnceEventListener (const std::string &event, Callback< Args... > callback)
	Add an event listener to an event. More...
bool	removeEventListener (const std::string &event, int id)
	Remove an event listener from an event. More...
bool	removeAllEventListeners (const std::string &event)
	Remove all event listeners of an event. More...
template<typename... Args>
void	emit (const std::string &event, Args...args)
	Fire an event. More...
bool	hasEvent (const std::string &event) const
	Check if an event exists or not. More...
std::size_t	getEventListenerCount (const std::string &event) const
	Get the number of event listeners currently registered to an event. More...
std::size_t	getEventsCount () const
	Get the current number of created events. More...
bool	hasEventListener (const std::string &event, int id) const
	Check if an event has a certain event listener. More...

Detailed Description

Class for creating and publishing events.

Note

There is no function for creating an event. Events are created when a listener/callback is added for the first time. All Subsequent event listeners will be added to the created event. Events are not fired automatically, a call to the emit function must be made to fire an event and notify event listeners

Definition at line 49 of file EventEmitter.h.

Constructor & Destructor Documentation

EventEmitter() [1/3]

ime::EventEmitter::EventEmitter ( )

default

Default constructor.

EventEmitter() [2/3]

ime::EventEmitter::EventEmitter

(

const EventEmitter &

)

Copy constructor.

EventEmitter() [3/3]

ime::EventEmitter::EventEmitter ( EventEmitter &&  )

noexcept

Move constructor.

Member Function Documentation

addEventListener()

template<typename... Args>

int ime::EventEmitter::addEventListener	(	const std::string &	event,
		Callback< Args... >	callback
	)

Add an event listener (callback) to an event.

Parameters

event	Event to add event listener to
callback	Function to execute when the event is fired

Returns

The event listener's identification number

Every event listener has a unique identification number. This number must be remembered in order to remove the event listener.

Note

If the same callback function is added multiple times, It will be treated as a unique event listener and hence given an identification number

addOnceEventListener()

template<typename ... Args>

int ime::EventEmitter::addOnceEventListener	(	const std::string &	event,
		Callback< Args... >	callback
	)

Add an event listener to an event.

Parameters

event	Event to add event listener to
callback	Function to execute when the event is fired

Returns

The event listener's identification number

The event listener will be invoked once and subsequently removed from the event. This means that the callback will only execute when an event is fired for the first time. To execute a callback each time the an event is fired

See also

addEventListener

emit()

template<typename... Args>

void ime::EventEmitter::emit	(	const std::string &	event,
		Args...	args
	)

Fire an event.

Parameters

event	Name of the event to fire
args	Arguments to be passed to event listeners

getEventListenerCount()

std::size_t ime::EventEmitter::getEventListenerCount

(

const std::string &

event

)

const

Get the number of event listeners currently registered to an event.

Parameters

event

Event to get number of event listeners for

Returns

The number of event listeners registered to an event or 0 if no such event exists

getEventsCount()

std::size_t ime::EventEmitter::getEventsCount

(

)

const

Get the current number of created events.

Returns

Current umber of events

hasEvent()

bool ime::EventEmitter::hasEvent

(

const std::string &

event

)

const

Check if an event exists or not.

Parameters

event

Name of the event to check

Returns

True if event exists or false if the event does not exist

hasEventListener()

bool ime::EventEmitter::hasEventListener	(	const std::string &	event,
		int	id
	)		const

Check if an event has a certain event listener.

Parameters

event	Name of the event
id	Identification number of the listener to be checked

Returns

True if the specified event has an event listener with the specified id, otherwise false

on()

template<typename... Args>

int ime::EventEmitter::on	(	const std::string &	event,
		Callback< Args... >	callback
	)

Add an event listener to an event.

Parameters

event	Event to add event listener to
callback	Function to execute when the event is fired

Returns

The event listener's identification number

This function does the same thing as the addEventListener() function. It just provides a slightly more readable syntax:

returnButton.on("click", showMainMenu); as opposed to
returnButton.addEventListener("click", showMainMenu);

operator=() [1/2]

EventEmitter& ime::EventEmitter::operator=

(

const EventEmitter &

)

Copy assignment operator.

operator=() [2/2]

EventEmitter& ime::EventEmitter::operator= ( EventEmitter &&  )

noexcept

Move assignment operator.

removeAllEventListeners()

bool ime::EventEmitter::removeAllEventListeners

(

const std::string &

event

)

Remove all event listeners of an event.

Parameters

event

Event to remove all listeners from

Returns

True if all listeners were removed, false if no such event exists

removeEventListener()

bool ime::EventEmitter::removeEventListener	(	const std::string &	event,
		int	id
	)

Remove an event listener from an event.

Parameters

event	Event to remove listener from
id	Identification number of the event listener to be removed

Returns

True if the event listener was removed from athe specified event or false if the specified event does exist or it does not have a listener with the given id

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The documentation for this class was generated from the following file:

• EventEmitter.h