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PNotifierTemplate< ParamType > Class Template Reference

The PNotifier and PNotifierFunction classes build a completely type safe mechanism for calling arbitrary member functions on classes. More...

#include <notifier.h>

Inheritance diagram for PNotifierTemplate< ParamType >:
Collaboration diagram for PNotifierTemplate< ParamType >:

Public Types

typedef
PNotifierFunctionTemplate
< ParamType > * 
FunctionPtr
 

Public Member Functions

 PNotifierTemplate (FunctionPtr func=NULL)
 Create a new notification function smart pointer. More...
 
virtual void operator() (PObject &notifier, ParamType extra) const
 Execute the call to the actual notification function on the object instance contained in this object. More...
 
void * GetTarget () const
 
- Public Member Functions inherited from PSmartPointer
 PSmartPointer (PSmartObject *obj=NULL)
 Create a new smart pointer instance and have it point to the specified PSmartObject instance. More...
 
 PSmartPointer (const PSmartPointer &ptr)
 Create a new smart pointer and point it at the data pointed to by the ptr parameter. More...
 
virtual ~PSmartPointer ()
 Destroy the smart pointer and decrement the reference count on the object being pointed to. More...
 
PSmartPointeroperator= (const PSmartPointer &ptr)
 Assign this pointer to the value specified in the ptr parameter. More...
 
virtual Comparison Compare (const PObject &obj) const
 Determine the relative rank of the pointers. More...
 
PBoolean IsNULL () const
 Determine if the smart pointer has been set to point to an actual object instance. More...
 
PSmartObjectGetObject () const
 Get the current value if the internal smart object pointer. More...
 
- Public Member Functions inherited from PObject
unsigned GetTraceContextIdentifier () const
 Get PTRACE context identifier. More...
 
void SetTraceContextIdentifier (unsigned id)
 
void GetTraceContextIdentifier (PObject &obj)
 
void GetTraceContextIdentifier (PObject *obj)
 
void SetTraceContextIdentifier (const PObject &obj)
 
void SetTraceContextIdentifier (const PObject *obj)
 
virtual ~PObject ()
 
virtual PObjectClone () const
 Create a copy of the class on the heap. More...
 
template<class CLS >
CLS * CloneAs () const
 As for Clone() but converts to specified type. More...
 
virtual PINDEX HashFunction () const
 This function yields a hash value required by the PDictionary class. More...
 
virtual Comparison CompareObjectMemoryDirect (const PObject &obj) const
 Determine the byte wise comparison of two objects. More...
 
bool operator== (const PObject &obj) const
 Compare the two objects. More...
 
bool operator!= (const PObject &obj) const
 Compare the two objects. More...
 
bool operator< (const PObject &obj) const
 Compare the two objects. More...
 
bool operator> (const PObject &obj) const
 Compare the two objects. More...
 
bool operator<= (const PObject &obj) const
 Compare the two objects. More...
 
bool operator>= (const PObject &obj) const
 Compare the two objects. More...
 
virtual const char * GetClass (unsigned ancestor=0) const
 Get the current dynamic type of the object instance. More...
 
PBoolean IsClass (const char *cls) const
 
virtual PBoolean InternalIsDescendant (const char *clsName) const
 Determine if the dynamic type of the current instance is a descendent of the specified class. More...
 
__inline const PObjectPTraceObjectInstance () const
 
virtual void PrintOn (ostream &strm) const
 Output the contents of the object to the stream. More...
 
virtual void ReadFrom (istream &strm)
 Input the contents of the object from the stream. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from PObject
static Comparison InternalCompareObjectMemoryDirect (const PObject *obj1, const PObject *obj2, PINDEX size)
 Internal function caled from CompareObjectMemoryDirect() More...
 
static const char * Class ()
 Get the name of the class as a C string. More...
 
static __inline const PObjectPTraceObjectInstance (const char *)
 
static __inline const PObjectPTraceObjectInstance (const PObject *obj)
 
- Protected Member Functions inherited from PObject
 PObject ()
 Constructor for PObject, made protected so cannot ever create one on its own. More...
 
- Protected Attributes inherited from PSmartPointer
PSmartObjectobject
 Object the smart pointer points to. More...
 
- Friends inherited from PObject

Detailed Description

template<typename ParamType>
class PNotifierTemplate< ParamType >

The PNotifier and PNotifierFunction classes build a completely type safe mechanism for calling arbitrary member functions on classes.

The "pointer to a member function" capability built into C++ makes the assumption that the function name exists in an ancestor class. If you wish to call a member function name that does {not} exist in any ancestor class, very type unsafe casting of the member functions must be made. Some compilers will even refuse to do it at all!

To overcome this problem, as this mechanism is highly desirable for callback functions in the GUI part of the PTLib library, these classes and a macro are used to create all the classes and declarations to use polymorphism as the link between the caller, which has no knowledege of the function, and the receiver object and member function.

This is most often used as the notification of actions being take by interactors in the PTLib library.

Member Typedef Documentation

template<typename ParamType>
typedef PNotifierFunctionTemplate<ParamType>* PNotifierTemplate< ParamType >::FunctionPtr

Constructor & Destructor Documentation

template<typename ParamType>
PNotifierTemplate< ParamType >::PNotifierTemplate ( FunctionPtr  func = NULL)
inline

Create a new notification function smart pointer.

Parameters
funcNotifier function to call.

Member Function Documentation

template<typename ParamType>
void* PNotifierTemplate< ParamType >::GetTarget ( ) const
inline
template<typename ParamType>
virtual void PNotifierTemplate< ParamType >::operator() ( PObject notifier,
ParamType  extra 
) const
inlinevirtual

Execute the call to the actual notification function on the object instance contained in this object.

This will make a polymorphic call to the function declared by the PDECLARE_NOTIFIER macro which in turn calls the required function in the destination object.

Parameters
notifierObject that is making the notification.
extraExtra information that may be passed to function.

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