PIObject Class Reference

This is base class for any classes which use events -> handlers mechanism. More...

Inheritance diagram for PIObject:

Public Member Functions
	PIObject (const PIString &name=PIString())
	Contructs PIObject with name "name".
PIString	name () const
	Returns object name.
virtual const char *	className () const
	Returns object class name.
bool	debug () const
	Return if debug of this object is active.
void	setName (const PIString &name)
	Set object name.
void	setDebug (bool debug)
	Set object debug active.
const PIMap< PIString, PIVariant > &	properties () const
	Returns properties of the object.
int	propertiesCount () const
	Returns properties count of the object.
PIVariant	property (const PIString &name) const
	Returns property with name "name".
void	setProperty (const PIString &name, const PIVariant &value)
	Set property with name "name" to "value". If there is no such property in object it will be added.
bool	isPropertyExists (const PIString &name) const
	Returns if property with name "name" exists.

Static Public Member Functions
static void	piDisconnect (PIObject *src, const PIString &sig)
	Disconnect object "src" from all connections with event name "sig".
static void	piDisconnect (PIObject *src)
	Disconnect object "src" from all connections, i.e. all connections where object "src" is emitter.
static PIObject *	findByName (const PIString &name)
	Returns PIObject* with name "name" or 0, if there is no object found.

Protected Member Functions
PIObject *	emitter () const
	Returns PIObject* which has raised an event. This value is correct only in definition of some event handler.
virtual void	propertyChanged (const PIString &name)
	Virtual function executes after property with name "name" has been changed.

Related Functions
(Note that these are not member functions.)
#define	piCoutObj
	Macro used for conditional (piDebug and PIObject::debug()) output to PICout for subclasses of PIObject.
#define	PIOBJECT(name)
	you should use this macro after class declaration to use EVENT and EVENT_HANDLER and correct piCoutObj output
#define	EVENT_HANDLER0(ret, name)   ret name()
	declare event handler "event" with name "name" and return type "ret", ret name()
#define	EVENT_HANDLER1(ret, name, type0, var0)   ret name(type0 var0)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0)
#define	EVENT_HANDLER2(ret, name, type0, var0, type1, var1)   ret name(type0 var0, type1 var1)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0, type1 var1)
#define	EVENT_HANDLER3(ret, name, type0, var0, type1, var1, type2, var2)   ret name(type0 var0, type1 var1, type2 var2)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0, type1 var1, type2 var2)
#define	EVENT_HANDLER4(ret, name, type0, var0, type1, var1, type2, var2, type3, var3)   ret name(type0 var0, type1 var1, type2 var2, type3 var3)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0, type1 var1, type2 var2, type3 var3)
#define	EVENT_HANDLER   EVENT_HANDLER0
	EVENT_HANDLER is synonym of EVENT_HANDLER0.
#define	EVENT_VHANDLER0(ret, name)   virtual ret name()
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name()
#define	EVENT_VHANDLER1(ret, name, type0, var0)   virtual ret name(type0 var0)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0)
#define	EVENT_VHANDLER2(ret, name, type0, var0, type1, var1)   virtual ret name(type0 var0, type1 var1)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1)
#define	EVENT_VHANDLER3(ret, name, type0, var0, type1, var1, type2, var2)   virtual ret name(type0 var0, type1 var1, type2 var2)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1, type2 var2)
#define	EVENT_VHANDLER4(ret, name, type0, var0, type1, var1, type2, var2, type3, var3)   virtual ret name(type0 var0, type1 var1, type2 var2, type3 var3)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1, type2 var2, type3 var3)
#define	EVENT_VHANDLER   EVENT_VHANDLER0
	EVENT_VHANDLER is synonym of EVENT_VHANDLER0.
#define	EVENT0(name)   void name();
	declare event "event" with name "name", void name();
#define	EVENT1(name, type0, var0)   void name(type0 var0);
	declare event "event" with name "name", void name(type0 var0);
#define	EVENT2(name, type0, var0, type1, var1)   void name(type0 var0, type1 var1);
	declare event "event" with name "name", void name(type0 var0, type1 var1);
#define	EVENT3(name, type0, var0, type1, var1, type2, var2)   void name(type0 var0, type1 var1, type2 var2);
	declare event "event" with name "name", void name(type0 var0, type1 var1, type2 var2);
#define	EVENT4(name, type0, var0, type1, var1, type2, var2, type3, var3)   void name(type0 var0, type1 var1, type2 var2, type3 var3);
	declare event "event" with name "name", void name(type0 var0, type1 var1, type2 var2, type3 var3);
#define	EVENT   EVENT0
	EVENT is synonym of EVENT0.
#define	CONNECT0(ret, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists
#define	CONNECT1(ret, type0, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists
#define	CONNECT2(ret, type0, type1, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists
#define	CONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists
#define	CONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists
#define	CONNECT   CONNECT0
	CONNECT is synonym of CONNECT0.
#define	WEAK_CONNECT0(ret, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists
#define	WEAK_CONNECT1(ret, type0, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists
#define	WEAK_CONNECT2(ret, type0, type1, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists
#define	WEAK_CONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists
#define	WEAK_CONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists
#define	WEAK_CONNECT   WEAK_CONNECT0
	WEAK_CONNECT is synonym of WEAK_CONNECT0.
#define	DISCONNECT0(ret, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"
#define	DISCONNECT1(ret, type0, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"
#define	DISCONNECT2(ret, type0, type1, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"
#define	DISCONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"
#define	DISCONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"
#define	DISCONNECT   DISCONNECT0
	DISCONNECT is synonym of DISCONNECT0.
#define	HANDLER(handler)
	Returns pointer to events handler "handler".

Detailed Description

This is base class for any classes which use events -> handlers mechanism.

Events and Event handlers

PIObject provide notification mechanism similar Qt but implemented on language capabilities without any special preprocessors or compilers. Any class inherits PIObject should use macro PIOBJECT() immediate after declaration to proper compile.

Event is a some abstract event that can be raised at any time. Event is a function but declared with special macro EVENT(). To raise event simply execute event function.

Event handler is a function but declared with special macro EVENT_HANDLER(). You can use event handlers as ordinary functions.

Main goal of this mechanism is perform abstract connections between various objects. This functionality provide macro CONNECT() which connect some event of first object to some event handler or event of second object. Each event can be connected any times to any event handlers.

Example:

class ObjectA: public PIObject {
    PIOBJECT(ObjectA)
public:
    EVENT_HANDLER1(void, handlerA, const PIString & , str) {piCoutObj << "handler A:" << str;}
    EVENT2(eventA2, int, i, float, f);
    EVENT1(eventA1, const PIString & , str);
};

class ObjectB: public PIObject {
    PIOBJECT(ObjectB)
public:
    EVENT_HANDLER2(void, handlerB, int, i, float, f) {piCoutObj << "handler B:" << i << "," << f;}
    EVENT1(eventB, PIString, str);
};

int main(int argc, char * argv[]) {
    ObjectA obj_a;
    ObjectB obj_b;
    
    CONNECT2(void, int, float, &obj_a, eventA2, &obj_b, handlerB);
    obj_a.eventA2(2, 0.5);
    
    CONNECT1(void, PIString, &obj_b, eventB, &obj_a, handlerA);
    obj_b.eventB("event to handler");
    
    CONNECT1(void, PIString, &obj_a, eventA1, &obj_b, eventB);
    obj_a.eventA1("event to event");
};

Result:

handler B: 2 , 0.5
handler A: event to handler
handler A: event to event