Bind class instance function to v8::FunctionTemplate

Question

I'm fairly new to C++ and v8 in general, and I wanted to build a native node.js addon, but now I'm stuck on something quite simple IMO, but I can't figure out what the issue is, the error message

C:\Path\To\Project\File.cpp(50): error C2664: 'v8::Local<v8::FunctionTemplate> v8::FunctionTemplate::New(v8::Isolate *,v8::FunctionCallback,v8::Local<v8::Value>,v8::Local<v8::Signature>,int,v8::ConstructorBehavior,v8::SideEffectType)': cannot convert argument 2 from 'v8::Local<v8::Value> (__cdecl *)(const v8::FunctionCallbackInfo<v8::Value> &)' to 'v8::FunctionCallback' [C:\Path\To\Project\build\node_gui.vcxproj]

is not that helpful.

I've got the following code,

v8::Local <v8::Object> Window::GetFunctions() {
    v8::Local <v8::Object> DrawFunctions = v8::Object::New(isolate);


    v8::Local <v8::FunctionTemplate> bgfnc = v8::FunctionTemplate::New(isolate, &Window::BackgroundCB);

    DrawFunctions->Set(v8::String::NewFromUtf8(isolate, "background"), bgfnc);

    return DrawFunctions;
}

void Window::Background(const v8::FunctionCallbackInfo <v8::Value> &args) {
    v8::Isolate *isolate = args.GetIsolate();
    renderer->Background(args[0]->NumberValue(), args[1]->NumberValue(), args[2]->NumberValue());
}

v8::Handle <v8::Value> BackgroundCB(const v8::FunctionCallbackInfo <v8::Value> &args) {
    return ((Window*)v8::External::Cast(*(args.Data())->Value())->Background());
}

I want to create an object that contains a list of functions, the functions' callbacks would be member functions of the Window class. I know this has been asked before here, which worked once using a non-member function but otherwise not.

Thanks

Sidenote: I've looked far and wide for v8 docs that are suitable for beginners, the nodesource ones don't explain what the parameters mean or rarely give a thorough example of how to use the function / class, if anyone knows some better docs, that would be great, thank you.

Answer 1

Thanks to the gracious and prompt help of the community, I was able to quickly and effortlessly resolve this issue. Turns out, when writing NodeJS addons, it's a good idea to use NodeJS's own N-API, as the documentation is simpler, clearer, and most importantly, existant.