Class that manages adding and deleting of observers with events. More...

#include <Libs/MRML/Core/vtkEventBroker.h>

Public Types
enum	EventMode { Synchronous, Asynchronous }
Public Member Functions
vtkObservation *	AddObservation (vtkObject subject, unsigned long event, vtkObject observer, vtkCallbackCommand *notify, float priority=0.0f)
vtkObservation *	AddObservation (vtkObject subject, const char event, const char *script)
void	CloseLogFile ()
virtual void	CompressCallDataOff ()
virtual void	CompressCallDataOn ()
vtkObservation *	DequeueObservation ()
virtual void	EventLoggingOff ()
virtual void	EventLoggingOn ()
int	GenerateGraphFile (const char *graphFile)
virtual int	GetCompressCallData ()
virtual int	GetEventLogging ()
virtual int	GetEventMode ()
const char *	GetEventModeAsString ()
virtual int	GetEventNestingLevel ()
virtual char *	GetLogFileName ()
vtkObservation *	GetNthObservation (int n)
vtkObservation *	GetNthQueuedObservation (int n)
int	GetNumberOfObservations ()
int	GetNumberOfQueuedObservations ()
std::vector< vtkObservation * >	GetObservations (vtkObject subject, unsigned long event=0, vtkObject observer=0, vtkCallbackCommand *notify=0)
vtkCollection *	GetObservationsForCallback (vtkCallbackCommand *callback)
vtkCollection *	GetObservationsForObserver (vtkObject *observer)
vtkCollection *	GetObservationsForSubject (vtkObject *subject)
std::vector< vtkObservation * >	GetObservationsForSubjectByTag (vtkObject *subject, unsigned long tag)
std::vector< vtkObservation * >	GetSubjectObservations (vtkObject *subject)
	Fast retrieve of all observations of a given subject.
virtual vtkTimerLog *	GetTimerLog ()
void	InvokeObservation (vtkObservation observation, unsigned long eid, void callData)
void	LogEvent (vtkObservation *observation)
void	OpenLogFile ()
void	PrintSelf (ostream &os, vtkIndent indent)
void	ProcessEvent (vtkObservation observation, vtkObject caller, unsigned long eid, void *callData)
void	ProcessEventQueue ()
void	QueueObservation (vtkObservation observation, unsigned long eid, void callData)
	Event queue processing.
void	RemoveObservation (vtkObservation *observation)
void	RemoveObservations (vtkObject subject, unsigned long event, vtkObject observer, vtkCallbackCommand *notify)
void	RemoveObservations (vtkObject subject, vtkObject observer)
void	RemoveObservations (vtkObject subject, unsigned long event, vtkObject observer)
void	RemoveObservations (std::vector< vtkObservation * >observations)
void	RemoveObservations (vtkObject *observer)
void	RemoveObservationsForSubjectByTag (vtkObject *subject, unsigned long tag)
virtual void	SetCompressCallData (int)
virtual void	SetEventLogging (int)
void	SetEventMode (int eventMode)
void	SetEventModeToAsynchronous ()
void	SetEventModeToSynchronous ()
virtual void	SetEventNestingLevel (int)
virtual void	SetLogFileName (const char *)
void	SetScriptHandler (void(scriptHandler)(const char script, void clientData), void clientData)
virtual void	SetTimerLog (vtkTimerLog *timerLog)
	vtkTypeRevisionMacro (vtkEventBroker, vtkObject)
Static Public Member Functions
static void	Callback (vtkObject caller, unsigned long eid, void clientData, void *callData)
static vtkEventBroker *	GetInstance ()
static vtkEventBroker *	New ()
Protected Types
typedef char *	KeyType
typedef std::map< KeyType, ObservationVector >	ObjectToObservationVectorMap
typedef std::vector < vtkObservation * >	ObservationVector
typedef vtkEventBroker	Self
Protected Member Functions
void	AttachObservation (vtkObservation *observation)
void	DetachObservation (vtkObservation *observation)
void	operator= (const vtkEventBroker &)
	vtkEventBroker ()
	vtkEventBroker (const vtkEventBroker &)
virtual	~vtkEventBroker ()
Static Protected Member Functions
static void	classFinalize ()
static void	classInitialize ()
Protected Attributes
int	CompressCallData
int	EventLogging
int	EventMode
int	EventNestingLevel
std::deque< vtkObservation * >	EventQueue
	The event queue of triggered but not-yet-invoked observations.
std::ofstream	LogFile
char *	LogFileName
ObjectToObservationVectorMap	ObserverMap
void(*	ScriptHandler )(const char script, void clientData)
void *	ScriptHandlerClientData
ObjectToObservationVectorMap	SubjectMap
	maps to manage quick lookup by object
vtkTimerLog *	TimerLog
Friends
class	vtkEventBrokerInitialize
class	vtkObservation
	vtkObservation can call these methods

Detailed Description

Class that manages adding and deleting of observers with events.

This class keeps track of observers and events added to each vtk object. It caches tags returned by AddObserver method so that observers can be removed properly. See also: http://wiki.na-mic.org/Wiki/index.php/Slicer3:EventBroker http://en.wikipedia.org/wiki/Observer_pattern Other interesting observer implementations: http://xlobject.sourceforge http://sigslot.sourceforge.net/ http://doc.trolltech.com/4.3/signalsandslots.html

Definition at line 49 of file vtkEventBroker.h.

Member Typedef Documentation

typedef char* vtkEventBroker::KeyType [protected]

Definition at line 260 of file vtkEventBroker.h.

typedef std::map< KeyType, ObservationVector > vtkEventBroker::ObjectToObservationVectorMap [protected]

Definition at line 262 of file vtkEventBroker.h.

typedef std::vector< vtkObservation * > vtkEventBroker::ObservationVector [protected]

Definition at line 261 of file vtkEventBroker.h.

typedef vtkEventBroker vtkEventBroker::Self [protected]

Definition at line 256 of file vtkEventBroker.h.

Member Enumeration Documentation

enum vtkEventBroker::EventMode

Event Queue processing modes

In synchronous mode, observations are invoked immediately when the event takes place. In asynchronous mode, observations are added to the event queue for later invocation.

Enumerator:

Synchronous
Asynchronous

Definition at line 173 of file vtkEventBroker.h.

Constructor & Destructor Documentation

vtkEventBroker::vtkEventBroker ( ) [protected]

virtual vtkEventBroker::~vtkEventBroker ( ) [protected, virtual]

vtkEventBroker::vtkEventBroker ( const vtkEventBroker & ) [protected]

Member Function Documentation

vtkObservation* vtkEventBroker::AddObservation	(	vtkObject *	subject,
		unsigned long	event,
		vtkObject *	observer,
		vtkCallbackCommand *	notify,
		float	priority = `0.0f`
	)

Adding and Removing Observation objects

Request that an observer be added to the subject (or "observee")

this is the "Attach" operation

vtkObservation* vtkEventBroker::AddObservation	(	vtkObject *	subject,
		const char *	event,
		const char *	script
	)

Scripted version of observation

creates an observation that will be invoked using the ScriptHandler method

void vtkEventBroker::AttachObservation ( vtkObservation * observation ) [protected]

Attach adds the observers to the object. Detach removes the observers These routines manage the internal datastructres and should be the only methods used to modified the internal Observations member Please note that they don't update the SubjectMap nor the ObserverMap.

static void vtkEventBroker::Callback	(	vtkObject *	caller,
		unsigned long	eid,
		void *	clientData,
		void *	callData
	)		`[static]`

the static function used by the command callback (used by vtkObservation)

each observation has a vtkCallbackCommand method which stores the pointer to the vtkObservation class as the clientData
the vtkObservation has a pointer to vtkEventBroker, which knows how to process that event for that Observation

static void vtkEventBroker::classFinalize ( ) [static, protected]

static void vtkEventBroker::classInitialize ( ) [static, protected]

Singleton management functions.

void vtkEventBroker::CloseLogFile ( )

virtual void vtkEventBroker::CompressCallDataOff ( ) [virtual]

virtual void vtkEventBroker::CompressCallDataOn ( ) [virtual]

two modes -

CompressCallDataOn: only keep the most recent call data. this means that if the observation is in the queue, replace the call data with the current value
CompressCallDataOff: maintain the list of all call data values, but only one unique entry for each Compression is ON by default

vtkObservation* vtkEventBroker::DequeueObservation ( )

void vtkEventBroker::DetachObservation ( vtkObservation * observation ) [protected]

virtual void vtkEventBroker::EventLoggingOff ( ) [virtual]

virtual void vtkEventBroker::EventLoggingOn ( ) [virtual]

Event Logging

Turn on event tracing (requires TraceFile)

int vtkEventBroker::GenerateGraphFile ( const char * graphFile )

Graph File

Write out the current list of observations in graphviz format (.dot)

virtual int vtkEventBroker::GetCompressCallData ( ) [virtual]

virtual int vtkEventBroker::GetEventLogging ( ) [virtual]

virtual int vtkEventBroker::GetEventMode ( ) [virtual]

const char* vtkEventBroker::GetEventModeAsString ( ) [inline]

Definition at line 190 of file vtkEventBroker.h.

virtual int vtkEventBroker::GetEventNestingLevel ( ) [virtual]

static vtkEventBroker* vtkEventBroker::GetInstance ( ) [static]

Return the singleton instance with no reference counting.

virtual char* vtkEventBroker::GetLogFileName ( ) [virtual]

vtkObservation* vtkEventBroker::GetNthObservation ( int n )

vtkObservation* vtkEventBroker::GetNthQueuedObservation ( int n )

int vtkEventBroker::GetNumberOfObservations ( )

Accessors for Observations

int vtkEventBroker::GetNumberOfQueuedObservations ( )

std::vector< vtkObservation *> vtkEventBroker::GetObservations	(	vtkObject *	subject,
		unsigned long	event = `0`,
		vtkObject *	observer = `0`,
		vtkCallbackCommand *	notify = `0`
	)

If event is != 0 , only observations matching the events are returned If observer is != 0 , only observations matching the observer are returned If notify is != 0, only observations matching the callback are are returned

vtkCollection* vtkEventBroker::GetObservationsForCallback ( vtkCallbackCommand * callback )

vtkCollection* vtkEventBroker::GetObservationsForObserver ( vtkObject * observer )

vtkCollection* vtkEventBroker::GetObservationsForSubject ( vtkObject * subject )

Description Accessors for intropsection Note: vtkCollection object is allocated internally and must be freed by the caller

std::vector< vtkObservation *> vtkEventBroker::GetObservationsForSubjectByTag	(	vtkObject *	subject,
		unsigned long	tag
	)

std::vector< vtkObservation *> vtkEventBroker::GetSubjectObservations ( vtkObject * subject )

Fast retrieve of all observations of a given subject.

virtual vtkTimerLog* vtkEventBroker::GetTimerLog ( ) [virtual]

void vtkEventBroker::InvokeObservation	(	vtkObservation *	observation,
		unsigned long	eid,
		void *	callData
	)

void vtkEventBroker::LogEvent ( vtkObservation * observation )

actually write to the log file (also manages state of the LogFile ivar based on the filename and the EventLogging variable)

static vtkEventBroker* vtkEventBroker::New ( ) [static]

This is a singleton pattern New. There will only be ONE reference to a vtkEventBroker object per process. Clients that call this must call Delete on the object so that the reference counting will work. The single instance will be unreferenced when the program exits.

void vtkEventBroker::OpenLogFile ( )

Open and close the log file

void vtkEventBroker::operator= ( const vtkEventBroker & ) [protected]

void vtkEventBroker::PrintSelf	(	ostream &	os,
		vtkIndent	indent
	)

void vtkEventBroker::ProcessEvent	(	vtkObservation *	observation,
		vtkObject *	caller,
		unsigned long	eid,
		void *	callData
	)

Process any event that comes from either subject or observer

void vtkEventBroker::ProcessEventQueue ( )

void vtkEventBroker::QueueObservation	(	vtkObservation *	observation,
		unsigned long	eid,
		void *	callData
	)

Event queue processing.

Event queue handling routines Note:

assume here that the information in a vtkObservation contains enough information for the observer to handle the event (that is, we don't pass the callData field of the event back) TODO: if the callData is needed, we will need another class/struct to go into the event queue that saves them

void vtkEventBroker::RemoveObservation ( vtkObservation * observation )

Remove observation from the broker and event queue

void vtkEventBroker::RemoveObservations ( std::vector< vtkObservation * > observations )

Remove all observations that match