Subj : Re: about defining object...
To   : netscape.public.mozilla.jseng
From : celleris@naver.com (Youngsun Jeong)
Date : Wed Oct 01 2003 03:02 am

>>JSObject* InitMyobjectClass(JSContext *cx, JSObject *obj)
>>{
>> JSObject *proto;
>>
>> proto = JS_InitClass(cx, obj, NULL, &my_class, NULL, 1, NULL,
>>my_method, NULL,NULL);
>> 


>There's your problem: you don't pass a non-null constructor parameter
>(after &my_class).

Yes, so I modified that. See below:

JSObject* InitMyobjectClass(...)
{
                    ...
  proto = JS_InitClass(cx, obj, NULL, &my_class, MyObj, 1, NULL,
my_method,  NULL, NULL);
                    ...
}

And I write a native constructor:

//native constructor
static JSBool
MyObj(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval
*rval)
{
    if(argc == 0)
    {
        obj = NULL;
    }
    else
    {
        if(!js_ValueToObject(cx, argv[0], &obj))
            return JS_FALSE;
    }
    if(!obj)
    {
        JS_ASSERT(!argc || JSVAL_IS_NULL(argv[0]) ||
JSVAL_IS_VOID(argv[0]));
        if (cx->fp->flags & JSFRAME_CONSTRUCTING)
            return JS_TRUE;
        obj = js_NewObject(cx, &my_class, NULL, NULL);
       
        if (!obj)
            return JS_FALSE;
    }
    *rval = OBJECT_TO_JSVAL(obj);
    return JS_TRUE;
}

Is that right? What value of "obj", "argv" and "argc"? 

>>"my_class" has method "my_plusAge()", doesn't have any properties.
>>And I add "InitMyobjectClass" to jsapi.c. See below:
>>
>>file name : jsapi.c 
>> ...
>>#include "myobject.h" //added
>> ...
>>JS_PUBLIC_API(JSBool)
>>JS_InitStandardClasses(JSContext *cx, JSObject *obj)
>>{ 
>> ... 
>> return js_InitArrayClass(cx, obj) &&
>> js_InitBooleanClass(cx, obj) &&
>> js_InitMathClass(cx, obj) &&
>> js_InitNumberClass(cx, obj) &&
>> js_InitStringClass(cx, obj) &&
>> InitMyobjectClass(cx, obj) && //added
>> 
>>

>Please don't do that. There's absolutely no reason. In *your* code, 
>that calls JS_InitStandardClasses, just call your class init function
>after JS_InitStandardClasses returns successfully.

Ok, I deleted that code.

>> ...
>>}
>>What is wrong?
>> 
>>

>See above, and more below.

>>And I want to know how do make the relation between "age" and
>>"plusAge()".
>> 

>Where do you call JS_SetPrivate on new objects of your class, to give
>them an "age" private datum? Since you pass NULL for the class 
>constructor, there's no chance for your code to associate an age with
>each object via JS_SetPrivate.

I don't know where should I call JS_SetPrivate because I don't know
where "age" private datum is passed. Please tell me how do that.

>What documentation are you studying, btw?

I'm studying "mozilla/js/src/README.html" and "JS Embedder's Guide "
on mozilla's js/spidermonkey page.

.