fge::Subscription Class Reference

This class is a useful utility to "link" multiple objects around a specific use with automatic lifetime management. More...

#include <C_subscription.hpp>

Inheritance diagram for fge::Subscription:

Public Types
using	SubscriberCount = unsigned int

Public Member Functions
	Subscription (fge::Subscription const &r)
	Subscription (fge::Subscription &&r) noexcept
virtual	~Subscription ()
	When the object is destroyed, it will detach all subscribers.
fge::Subscription &	operator= (fge::Subscription const &r)
fge::Subscription &	operator= (fge::Subscription &&r) noexcept

Protected Member Functions
virtual void	onDetach (fge::Subscriber *subscriber)=0
	Callback called when a subscriber is detached.
void	detachAll ()
	Detach all subscribers.
bool	detach (fge::Subscriber *subscriber)
	Detach a specific subscriber.
fge::Subscription::SubscriberCount	detachOnce (fge::Subscriber *subscriber)
	Detach only once a specific subscriber.
fge::Subscription::SubscriberCount	attach (fge::Subscriber *subscriber)
	Attach a specific subscriber.
fge::Subscription::SubscriberCount	getCount (fge::Subscriber *subscriber) const
	Get the SubscriberCount of a specific subscriber.

Friends
class	fge::Subscriber

Detailed Description

This class is a useful utility to "link" multiple objects around a specific use with automatic lifetime management.

A good example is the callback system. When inheriting from Subscriber, you will be able to subscribe a function to a CallbackHandler (inheriting from Subscription) and you don't have to worry about unsubscribing it when the object is destroyed.

A nullptr subscriber mean that you are subscribing something that is not class related. (sort of a global scope).

Alone this class will not do much as you have to implement the required functionality around it.

See also

CallbackHandler

Constructor & Destructor Documentation

Subscription()

fge::Subscription::Subscription ( fge::Subscription const & r )

inline

Warning

Empty copy constructor as it's not permitted (does nothing)

~Subscription()

virtual fge::Subscription::~Subscription ( )

inlinevirtual

When the object is destroyed, it will detach all subscribers.

Member Function Documentation

attach()

fge::Subscription::SubscriberCount fge::Subscription::attach ( fge::Subscriber * subscriber )

protected

Attach a specific subscriber.

You can't directly attach a nullptr global scope subscriber. But if you do, this function will do nothing and return 1 as the SubscriberCount.

Parameters

subscriber

The subscriber to attach

Returns

The SubscriberCount

detach()

bool fge::Subscription::detach ( fge::Subscriber * subscriber )

protected

Detach a specific subscriber.

Detaching a nullptr global scope subscriber will do nothing.

Parameters

subscriber

The subscriber to detach

Returns

true if the subscriber was detached, false otherwise

detachAll()

void fge::Subscription::detachAll ( )

protected

Detach all subscribers.

detachOnce()

fge::Subscription::SubscriberCount fge::Subscription::detachOnce ( fge::Subscriber * subscriber )

protected

Detach only once a specific subscriber.

You can attach a subscriber multiple times and it will augment the SubscriberCount. This function will only detach one time the subscriber and decrement the SubscriberCount. If the SubscriberCount is 0, the subscriber will be detached.

Parameters

subscriber

The subscriber to detach

Returns

The remaining SubscriberCount

getCount()

fge::Subscription::SubscriberCount fge::Subscription::getCount ( fge::Subscriber * subscriber ) const

protected

Get the SubscriberCount of a specific subscriber.

Parameters

subscriber

The subscriber to get the SubscriberCount

Returns

The SubscriberCount

onDetach()

virtual void fge::Subscription::onDetach ( fge::Subscriber * subscriber )

protectedpure virtual

Callback called when a subscriber is detached.

The subscriber, at this point, can't be nullptr.

Parameters

subscriber

The subscriber that was detached

Implemented in fge::CallbackHandler< Types >, fge::CallbackHandler< ClientSharedPtr const & >, fge::CallbackHandler< fge::Event const &, SDL_AudioDeviceEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_CommonEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_ControllerAxisEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_ControllerButtonEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_ControllerDeviceEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_DollarGestureEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_DropEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_EventType, fge::GuiElementContext & >, fge::CallbackHandler< fge::Event const &, SDL_JoyAxisEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_JoyBallEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_JoyButtonEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_JoyDeviceEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_JoyHatEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_KeyboardEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_MouseButtonEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_MouseButtonEvent const &, fge::GuiElementContext & >, fge::CallbackHandler< fge::Event const &, SDL_MouseMotionEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_MouseMotionEvent const &, fge::GuiElementContext & >, fge::CallbackHandler< fge::Event const &, SDL_MouseWheelEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_MouseWheelEvent const &, fge::GuiElementContext & >, fge::CallbackHandler< fge::Event const &, SDL_MultiGestureEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_QuitEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_SysWMEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_TextEditingEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_TextInputEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_TouchFingerEvent const & >, fge::CallbackHandler< fge::Event const &, SDL_WindowEvent const & >, fge::CallbackHandler< fge::GuiElementHandler const &, fge::Vector2f const & >, fge::CallbackHandler< fge::net::Client & >, fge::CallbackHandler< fge::ObjButton * >, fge::CallbackHandler< fge::ObjSelectBox &, std::size_t >, fge::CallbackHandler< fge::ObjTextInputBox & >, fge::CallbackHandler< fge::ObjWindow & >, fge::CallbackHandler< fge::Scene & >, fge::CallbackHandler< fge::Scene &, fge::ObjectDataShared const & >, fge::CallbackHandler< fge::Scene &, fge::ObjectPlan >, fge::CallbackHandler< fge::Scene const &, fge::RenderTarget & >, fge::CallbackHandler< fge::TaskHandler & >, fge::CallbackHandler< fge::Timer & >, fge::CallbackHandler< fge::Vector2f const & >, and fge::CallbackHandler< float >.

operator=()

fge::Subscription & fge::Subscription::operator= ( fge::Subscription const & r )

inline

Warning

Empty copy operator as it's not permitted (does nothing)

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

• C_subscription.hpp