Hi, I'm using a C++ lambda to represent the callback state for a Javascript
callback and wanted to solicit some feedback on this approach. I thought
this would be an elegant way to set up the C++ binding. Here is some
example code from the Javascript side:
var i = new Thing();
i.callback = function (arg1, arg2) {
// do stuff
};
i.callback will be called back whenever an interesting event happens to the
"i" object in C++ world.
Here is C++ binding code to capture the object *i*, the *function* on it,
and the *context*. (My application is single-threaded.) Null tests etc.
edited out.
void ThingCallbackSetter (Local <String> property, Local <Value> value,
const PropertyCallbackInfo<void> &info)
{ Isolate* i = Isolate::GetCurrent();
HandleScope scope (i);
Handle<Object> o = info . This ();
Thing* thing = //unwrap the C++ object
// Make persistent versions of object, function, and context
Persistent <v8::Object, CopyablePersistentTraits<Object> > obj (i, o);
Persistent <v8::Function, CopyablePersistentTraits<Function> > fn (i,
Handle<v8::Function>::Cast (value));
Persistent <v8::Context, CopyablePersistentTraits<Context> > ctxt (i,
i->GetCurrentContext());
thing -> AwaitCallback ([obj, fn, ctxt] (Type1 * a0, Type1 * a1, Type3 *
a2)
{ Isolate* i = Isolate::GetCurrent();
HandleScope _ (i);
// Make local versions of persistents
Handle <Context> ct = Local <Context>::New (i, ctxt);
Context::Scope context_scope (ct);
Handle <Function> local_fn = Local <Function>::New (i, fn);
Handle <Object> local_obj = Local <Object>::New (i, obj);
Handle <Value> argv[ 2 ] = {to_js (a1), to_js (a2)};
local_fn -> Call (local_obj, 2, argv);
}
);
}
This works, but I feel the code is more gnarly than I would like, and I
might be making outright mistakes here. Any ideas on how to streamline it?
thanks,
Brandon
--
--
v8-users mailing list
v8-users@googlegroups.com
http://groups.google.com/group/v8-users
---
You received this message because you are subscribed to the Google Groups
"v8-users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to v8-users+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
