Ufe::Subject Class Reference

Observer pattern Subject class. More...

#include <subject.h>

Inheritance diagram for Ufe::Subject:

Public Member Functions
	Subject ()
	Constructor. More...
	Subject (const Subject &)
	Copy constructor. Observers are not copied. More...
	Subject (Subject &&)
	Move constructor. Observers are not moved. More...
virtual	~Subject ()
	Destructor. More...
Subject &	operator= (const Subject &)
	Assignment operator. Does nothing, as observers are not copied. More...
Subject &	operator= (Subject &&)
	Move assignment operator. Does nothing, as observers are not moved. More...
bool	addObserver (const Observer::Ptr &obs)
bool	removeObserver (const Observer::Ptr &obs)
bool	hasObserver (const Observer::Ptr &obs) const
std::size_t	nbObservers () const
virtual void	notify (const Notification &notification)
virtual bool	inCompositeNotification () const

Protected Member Functions
virtual void	beginNotificationGuard ()
	Notification guard interface. Implementation in this class is a no-op. More...
virtual void	endNotificationGuard ()

Private Types
typedef std::set< Observer::WeakPtr, std::owner_less< Observer::WeakPtr > >	Observers

Private Member Functions
void	cleanObservers (const Observers &dead)

Private Attributes
Observers	fObservers

Friends
class	NotificationGuard

Detailed Description

Observer pattern Subject class.

This class implements the Subject in the Observer Pattern:

https://en.wikipedia.org/wiki/Observer_pattern

Observers are held by weak pointer. The order in which observers are notified is unspecified, implementation dependent, and can change at any time. Observers should NOT rely on the order in which they are added to a Subject and assume they will be called in the same order.

The semantics of Subject under copy, assignment, move, and move assignment are that observers are not copied or moved. As compared to preventing copying, this provides flexibility for derived classes to support the value-based semantics of copy, as well as efficient support of temporary objects with move.

Definition at line 40 of file subject.h.

Member Typedef Documentation

Observers

typedef std::set<Observer::WeakPtr, std::owner_less<Observer::WeakPtr> > Ufe::Subject::Observers

private

Definition at line 108 of file subject.h.

Constructor & Destructor Documentation

Subject() [1/3]

Ufe::Subject::Subject

(

)

Constructor.

Subject() [2/3]

Ufe::Subject::Subject

(

const Subject &

)

Copy constructor. Observers are not copied.

Subject() [3/3]

Ufe::Subject::Subject

(

Subject &&

)

Move constructor. Observers are not moved.

~Subject()

virtual Ufe::Subject::~Subject ( )

virtual

Destructor.

Member Function Documentation

addObserver()

bool Ufe::Subject::addObserver

(

const Observer::Ptr &

obs

)

Add the argument Observer to this subject. Does nothing and returns false if the Observer is already present.

Parameters

obs	Observer to add to Subject.

Returns

True if the Observer has been added to Subject.

beginNotificationGuard()

virtual void Ufe::Subject::beginNotificationGuard ( )

protectedvirtual

Notification guard interface. Implementation in this class is a no-op.

Reimplemented in Ufe::ObservableSelection, and Ufe::Scene.

cleanObservers()

void Ufe::Subject::cleanObservers ( const Observers &  dead )

private

Remove dead observers.

Parameters

dead	Observers to remove.

endNotificationGuard()

virtual void Ufe::Subject::endNotificationGuard ( )

protectedvirtual

Reimplemented in Ufe::ObservableSelection, and Ufe::Scene.

hasObserver()

bool Ufe::Subject::hasObserver

(

const Observer::Ptr &

obs

)

const

Returns

True if this subject has the argument observer.

inCompositeNotification()

virtual bool Ufe::Subject::inCompositeNotification ( ) const

virtual

Composite notification predicate. Implementation in this class returns false.

Returns

True if this subject is collecting notifications into a composite notification.

Reimplemented in Ufe::ObservableSelection, and Ufe::Scene.

nbObservers()

std::size_t Ufe::Subject::nbObservers

(

)

const

Returns

Number of observers.

notify()

virtual void Ufe::Subject::notify ( const Notification &  notification )

virtual

Notify observers. Not protected to simplify Python bindings.

Parameters

notification

Notification to notify.

Reimplemented in Ufe::Scene.

operator=() [1/2]

Subject & Ufe::Subject::operator=

(

const Subject &

)

Assignment operator. Does nothing, as observers are not copied.

operator=() [2/2]

Subject & Ufe::Subject::operator=

(

Subject &&

)

Move assignment operator. Does nothing, as observers are not moved.

removeObserver()

bool Ufe::Subject::removeObserver

(

const Observer::Ptr &

obs

)

Remove the argument Observer from this subject. Returns false if the observer isn't found.

Parameters

obs	Observer to remove from Subject.

Returns

True if the Observer has been removed from Subject.

Friends And Related Function Documentation

NotificationGuard

friend class NotificationGuard

friend

Definition at line 101 of file subject.h.

Member Data Documentation

fObservers

Observers Ufe::Subject::fObservers

private

Definition at line 114 of file subject.h.

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

• common/include/ufe/subject.h