itk::EventObject Class Reference
[ITK System Objects]

Abstraction of the Events used to communicating among filters and with GUIs. More...

#include <itkEventObject.h>

Inheritance diagram for itk::EventObject:

[legend]

List of all members.

Public Member Functions
	EventObject ()
	EventObject (const EventObject &)
virtual	~EventObject ()
virtual EventObject *	MakeObject () const =0
virtual void	Print (std::ostream &os) const
virtual const char *	GetEventName (void) const =0
virtual bool	CheckEvent (const EventObject *) const =0
Protected Member Functions
virtual void	PrintSelf (std::ostream &os, Indent indent) const
virtual void	PrintHeader (std::ostream &os, Indent indent) const
virtual void	PrintTrailer (std::ostream &os, Indent indent) const
Private Member Functions
typedef EventObject *	EventFactoryFunction ()
void	operator= (const EventObject &)

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Detailed Description

Abstraction of the Events used to communicating among filters and with GUIs.

EventObject provides a standard coding for sending and receiving messages indicating things like the initiation of processes, end of processes, modification of filters.

EventObjects form a hierarchy similar to the itk::ExceptionObject allowing to factorize common events in a tree-like structure. Higher detail can be assigned by users by subclassing existing itk::EventObjects.

EventObjects are used by itk::Command and itk::Object for implementing the Observer/Subject design pattern. Observers register their interest in particular kinds of events produced by a specific itk::Object. This mechanism decouples classes among them.

As opposed to itk::Exception, itk::EventObject does not represent error states, but simply flow of information allowing to trigger actions as a consequence of changes occurring in state on some itk::Objects.

itk::EventObject carries information in its own type, it relies on the appropiate use of the RTTI (Run Time Type Information).

A set of standard EventObjects is defined near the end of itkEventObject.h.

See also:

itk::Command

itk::ExceptionObject

Definition at line 58 of file itkEventObject.h.

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Constructor & Destructor Documentation

itk::EventObject::EventObject

(

)

[inline]

Constructor and copy constructor. Note that these functions will be called when children are instantiated.

Definition at line 63 of file itkEventObject.h.

{}

virtual itk::EventObject::~EventObject

(

)

[inline, virtual]

Virtual destructor needed

Definition at line 68 of file itkEventObject.h.

{}

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Member Function Documentation

virtual EventObject* itk::EventObject::MakeObject

(

)

const [pure virtual]

Create an Event of this type This method work as a Factory for creating events of each particular type.

Implemented in itk::TreeChangeEvent< TTreeType >, itk::TreeNodeChangeEvent< TTreeType >, itk::TreeAddEvent< TTreeType >, itk::TreeRemoveEvent< TTreeType >, and itk::TreePruneEvent< TTreeType >.

void itk::EventObject::Print

(

std::ostream &

os

)

const [virtual]

Print Event information. This method can be overridden by specific Event subtypes. The default is to print out the type of the event.

Definition at line 24 of file itkEventObject.cxx.

References itk::Indent::GetNextIndent().

{
  Indent indent;
  
  this->PrintHeader(os,0); 
  this->PrintSelf(os, indent.GetNextIndent());
  this->PrintTrailer(os,0);
}  

virtual const char* itk::EventObject::GetEventName

(

void

)

const [pure virtual]

Return the StringName associated with the event.

Implemented in itk::TreeChangeEvent< TTreeType >, itk::TreeNodeChangeEvent< TTreeType >, itk::TreeAddEvent< TTreeType >, itk::TreeRemoveEvent< TTreeType >, and itk::TreePruneEvent< TTreeType >.

virtual bool itk::EventObject::CheckEvent

(

const EventObject *

)

const [pure virtual]

Check if given event matches or derives from this event.

void itk::EventObject::PrintSelf	(	std::ostream &	os,
		Indent	indent
	)			const [protected, virtual]

Methods invoked by Print() to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Definition at line 57 of file itkEventObject.cxx.

{
}

void itk::EventObject::PrintHeader	(	std::ostream &	os,
		Indent	indent
	)			const [protected, virtual]

Define a default print header for all objects.

Definition at line 38 of file itkEventObject.cxx.

{
  os << std::endl;
  os << indent << "itk::" << this->GetEventName() << " (" << this << ")\n";
}

void itk::EventObject::PrintTrailer	(	std::ostream &	os,
		Indent	indent
	)			const [protected, virtual]

Define a default print trailer for all objects.

Definition at line 50 of file itkEventObject.cxx.

{
  os << indent << std::endl;
}

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

• itkEventObject.h
• itkEventObject.cxx