#ifndef APP_GadgetCV_H
#define APP_GadgetCV_H
/******************************************************************************
 **
 **	C++ Class Library for the Amiga© system software.
 **
 **	Copyright (C) 1994 by Armin Vogt  **  EMail: armin@uni-paderborn.de
 **	All Rights Reserved.
 **
 **	$VER: apphome:APlusPlus/intuition/GadgetCV.h 1.04 (04.05.94) $
 **	
 ******************************************************************************/


class GWindow;

extern "C" {
#include <intuition/intuition.h>
#include <libraries/gadtools.h>
}
#include <APlusPlus/intuition/GWindow.h>
#include <APlusPlus/graphics/GraphicObject.h>
#include <APlusPlus/intuition/IntuiMessageC.h>


/******************************************************************************************
         » GadgetCV class «   virtual base class

   defines all methods that must be implemented for every derived gadget class to work
   together with the GWindow class.
   A virtual callback method is assigned to receive IntuiMessage events sent to the gadget.

 ******************************************************************************************/

class GadgetCV : public GraphicObject
{
	friend GWindow;
   friend IntuiMessageC;
	private:
		static GWindow *redrawSelfHomeWindow;
		
   protected:
		GadgetCV(GraphicObject *owner,AttrList& attrs)
      : GraphicObject(owner,attrs) { }
				
		struct Gadget *storeGadget(struct Gadget *);
      // store the created gadget address in GadgetCV.
      
		struct Gadget *gadgetPtr() { return (struct Gadget*)IObject(); }
      // the shadowed gadget or the first gadget in a list of gadgets is stored in gadgetPtr().
		
		struct Gadget *getGT_Context();	// give GadTools gadgets their context
		
		BOOL forceActiveGadget(const IntuiMessageC *imsg);		
		// gadget stays active after GADGETUP msg ONLY if msg was not caused by the user activating 
		// another gadget (in that case returns FALSE)!
		
		GWindow *getHomeWindow();
		// get GWindow that is direct or indirect owner of this gadget
		
   public:
      virtual ~GadgetCV() { };

      virtual APTR redrawSelf(GWindow *homeWindow,ULONG& returnType)	// inherited from GraphicObject
		{
			return GraphicObject::redrawSelf(homeWindow,returnType);  
		}         
		/** called when window size has been changed after GraphicObject has been adjusted.
       ** The gadget/gadgetlist is removed from the window's gadgetlist when this method is called.
       ** The gadget structure shadowed by the GadgetCV object has to be returned, also the type
       ** of the gadget (Standart,Boopsi,GadTools).
       ** In case of a list of gadgets the gadgets must be linked together (do not forget
       ** the ending null in the last gadgets NextGadget entry!) and then returned
       ** to be linked to the window again.
       **/
			 
      virtual void callback(const IntuiMessageC*)=0;
		/** Here is your way of receiving events from 'this' gadget: overload callback method.
		 ** In further derived classes your callback will have to call the callback of the direct
		 ** base class of your Gadget class. Look at the description of this base class to know
		 ** when to call and why.
		 **/
		 
      ULONG setAttributes(AttrList& attrs) { return GraphicObject::setAttributes(attrs); }
		ULONG getAttribute(Tag,ULONG&);
};

#endif