Subj : Re: Properties and Objects
To   : netscape.public.mozilla.jseng
From : eboli@hotdak.net (Joseph Smith)
Date : Wed Dec 03 2003 04:13 am

Hey, 

I give up :) I am willing to do this any way possible i am just
running out of time to get it done, i have read documentation and am
still not getting what i am missing, so I created the following two
classes *mostly* as per an online tutorial {parent, child};

Parent has an array of JSChilderen, when its created it creates a
bunch of new JSChilderen, and i am trying to use getProperty() to
simply tell the parent object to call the child objects output
function (ie from a script, var p = new Parent(); p.child.output;)

I have included the classes to show you what i am trying to do, if you
can explain how to pass in this fashion would be great help :)
Also if you can exain how this happens can you also show me how to go
from the static m_Childeren[0] that i am using for testing purposes,
into an index generated from the calling function (ie var p = new
Parent; p.child[40000].output) for example???

class JSChild
{
	public:
		JSChild()
		{
	
		}
	
		virtual ~JSChild()
		{

		}

		static JSBool JSGetProperty(JSContext *cx, JSObject *obj, jsval id,
jsval *vp);
		static JSBool JSSetProperty(JSContext *cx, JSObject *obj, jsval id,
jsval *vp);
		static JSBool JSConstructor(JSContext *cx, JSObject *obj, uintN
argc, jsval *argv, jsval *rval);
		static void JSDestructor(JSContext *cx, JSObject *obj);

		static JSObject* JSInit(JSContext *cx, JSObject *obj, JSObject
*proto = NULL);
		static JSClass Child_class;	
		
		static JSBool OutputDebugString(JSContext *cx, JSObject *obj, uintN
argc, jsval *argv, jsval *rval);

	private:

		static JSPropertySpec Child_properties[];
		static JSFunctionSpec Child_methods[];

		enum
		{

		};
};

JSPropertySpec JSChild::Child_properties[] = 
{ 
	{ 0 } 
};

JSFunctionSpec JSChild::Child_methods[] = 
{ 
	{ "output", OutputDebugString, 0, 0, 0 }, 
	{ 0, 0, 0, 0, 0 } 
};

JSClass JSChild::Child_class = 
{	"Child", 
	JSCLASS_HAS_PRIVATE, 
	JS_PropertyStub, 
	JS_PropertyStub, 
	JSChild::JSGetProperty, 
	JSChild::JSSetProperty, 
	JS_EnumerateStub, 
	JS_ResolveStub, 
	JS_ConvertStub, 
	JSChild::JSDestructor
};

JSBool JSChild::JSConstructor(JSContext *cx, JSObject *obj, uintN,
jsval *, jsval *)
{
	JS_SetPrivate(cx, obj, (void*)new JSChild);
	return JS_TRUE;
}

void JSChild::JSDestructor(JSContext *cx, JSObject *obj)
{
	delete (JSChild*)JS_GetPrivate(cx, obj);
}

JSObject *JSChild::JSInit(JSContext *cx, JSObject *obj, JSObject
*proto)
{
   	JSObject *newProtoObj = JS_InitClass(cx, obj, proto, &Child_class,
JSChild::JSConstructor, 0, NULL, JSChild::Child_methods, NULL, NULL);
	JS_DefineProperties(cx, newProtoObj, JSChild::Child_properties);
	return newProtoObj;
}

JSBool JSChild::JSGetProperty(JSContext *, JSObject *, jsval, jsval *)
{
	return JS_TRUE;
}

JSBool JSChild::JSSetProperty(JSContext *, JSObject *, jsval , jsval
*)
{
	return JS_TRUE;
}

JSBool JSChild::OutputDebugString(JSContext *, JSObject *, uintN,
jsval *, jsval *)
{
	#ifdef __WXMSW__
		::OutputDebugString(wxT("Testing\n"));
	#else 
		fputs("Testing", stderr);
	#endif
	return JS_TRUE;
}


class JSParent
{
	public:
		JSParent()
		{
			for (int i = 0; i < 10; i++)
			{
				m_Childeren[i] = new JSChild();
			}
		}
	
		virtual ~JSParent()
		{

		}

		JSChild* getJSChild(int index)
		{
			return m_Childeren[index];
		}

		static JSBool JSGetProperty(JSContext *cx, JSObject *obj, jsval id,
jsval *vp);
		static JSBool JSSetProperty(JSContext *cx, JSObject *obj, jsval id,
jsval *vp);
		static JSBool JSConstructor(JSContext *cx, JSObject *obj, uintN
argc, jsval *argv, jsval *rval);
		static void JSDestructor(JSContext *cx, JSObject *obj);

		static JSObject* JSInit(JSContext *cx, JSObject *obj, JSObject
*proto = NULL);
		static JSClass Parent_class;	
		

	private:
		
		JSChild* m_Childeren[10];
 		
		static JSPropertySpec Parent_properties[];
		static JSFunctionSpec Parent_methods[];

		enum
		{
			child_prop
		};
};

JSPropertySpec JSParent::Parent_properties[] = 
{ 
    { "child", child_prop, JSPROP_ENUMERATE },
	{ 0 } 
};

JSFunctionSpec JSParent::Parent_methods[] = 
{ 
	{ 0, 0, 0, 0, 0 } 
};

JSClass JSParent::Parent_class = 
{	"Parent", 
	JSCLASS_HAS_PRIVATE, 
	JS_PropertyStub, 
	JS_PropertyStub, 
	JSParent::JSGetProperty, 
	JSParent::JSSetProperty, 
	JS_EnumerateStub, 
	JS_ResolveStub, 
	JS_ConvertStub, 
	JSParent::JSDestructor
};

JSBool JSParent::JSConstructor(JSContext *cx, JSObject *obj, uintN,
jsval *, jsval *)
{
	JS_SetPrivate(cx, obj, (void*)new JSParent);
	return JS_TRUE;
}

void JSParent::JSDestructor(JSContext *cx, JSObject *obj)
{
	delete (JSParent*)JS_GetPrivate(cx, obj);
}

JSObject *JSParent::JSInit(JSContext *cx, JSObject *obj, JSObject
*proto)
{
   	JSObject *newProtoObj = JS_InitClass(cx, obj, proto,
&Parent_class, JSParent::JSConstructor, 0, NULL,
JSParent::Parent_methods, NULL, NULL);
	JS_DefineProperties(cx, newProtoObj, JSParent::Parent_properties);
	return newProtoObj;
}

JSBool JSParent::JSGetProperty(JSContext *cx, JSObject *obj, jsval id,
jsval *vp)
{
	if (JSVAL_IS_INT(id)) 
	{
		JSParent *p = (JSParent *) JS_GetPrivate(cx, obj);
		p=p; // Keep compiler happy
        switch (JSVAL_TO_INT(id)) 
		{
			case child_prop:
			{
				// How do i return our m_childeren[index] object???
				// What i tried before to no avail using static [index] will
eventually use a
				   wxHashArray or something to that extent
				*vp = OBJECT_TO_JSVAL(p->getJSChild(0));
			}
		}
	}
	else
	{
		return JS_FALSE;
	}
	
	return JS_TRUE;
}

JSBool JSParent::JSSetProperty(JSContext *, JSObject *, jsval , jsval
*)
{
	return JS_TRUE;
}


Thanks again for at least reading and any help you may offer, and I
also finally picked up on the point you were making reguarding the use
of [] for an array of objects vs () :) (WHACKS SELF IN THE HEAD) :)


Joseph

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