electron/native_mate/object_template_builder.h
2014-04-15 11:34:07 +08:00

125 lines
4.7 KiB
C++

// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE.chromium file.
#ifndef NATIVE_MATE_OBJECT_TEMPLATE_BUILDER_H_
#define NATIVE_MATE_OBJECT_TEMPLATE_BUILDER_H_
#include "base/bind.h"
#include "base/callback.h"
#include "base/strings/string_piece.h"
#include "native_mate/converter.h"
#include "native_mate/function_template.h"
#include "native_mate/template_util.h"
#include "v8/include/v8.h"
namespace mate {
namespace {
// Base template - used only for non-member function pointers. Other types
// either go to one of the below specializations, or go here and fail to compile
// because of base::Bind().
template<typename T, typename Enable = void>
struct CallbackTraits {
static v8::Handle<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate,
T callback) {
return CreateFunctionTemplate(isolate, base::Bind(callback));
}
};
// Specialization for base::Callback.
template<typename T>
struct CallbackTraits<base::Callback<T> > {
static v8::Handle<v8::FunctionTemplate> CreateTemplate(
v8::Isolate* isolate, const base::Callback<T>& callback) {
return CreateFunctionTemplate(isolate, callback);
}
};
// Specialization for member function pointers. We need to handle this case
// specially because the first parameter for callbacks to MFP should typically
// come from the the JavaScript "this" object the function was called on, not
// from the first normal parameter.
template<typename T>
struct CallbackTraits<T, typename enable_if<
is_member_function_pointer<T>::value>::type> {
static v8::Handle<v8::FunctionTemplate> CreateTemplate(v8::Isolate* isolate,
T callback) {
return CreateFunctionTemplate(isolate, base::Bind(callback),
HolderIsFirstArgument);
}
};
// This specialization allows people to construct function templates directly if
// they need to do fancier stuff.
template<>
struct CallbackTraits<v8::Handle<v8::FunctionTemplate> > {
static v8::Handle<v8::FunctionTemplate> CreateTemplate(
v8::Handle<v8::FunctionTemplate> templ) {
return templ;
}
};
} // namespace
// ObjectTemplateBuilder provides a handy interface to creating
// v8::ObjectTemplate instances with various sorts of properties.
class ObjectTemplateBuilder {
public:
explicit ObjectTemplateBuilder(
v8::Isolate* isolate,
v8::Local<v8::ObjectTemplate> templ = v8::ObjectTemplate::New());
~ObjectTemplateBuilder();
// It's against Google C++ style to return a non-const ref, but we take some
// poetic license here in order that all calls to Set() can be via the '.'
// operator and line up nicely.
template<typename T>
ObjectTemplateBuilder& SetValue(const base::StringPiece& name, T val) {
return SetImpl(name, ConvertToV8(isolate_, val));
}
// In the following methods, T and U can be function pointer, member function
// pointer, base::Callback, or v8::FunctionTemplate. Most clients will want to
// use one of the first two options. Also see mate::CreateFunctionTemplate()
// for creating raw function templates.
template<typename T>
ObjectTemplateBuilder& SetMethod(const base::StringPiece& name,
const T& callback) {
return SetImpl(name, CallbackTraits<T>::CreateTemplate(isolate_, callback));
}
template<typename T>
ObjectTemplateBuilder& SetProperty(const base::StringPiece& name,
const T& getter) {
return SetPropertyImpl(name,
CallbackTraits<T>::CreateTemplate(isolate_, getter),
v8::Local<v8::FunctionTemplate>());
}
template<typename T, typename U>
ObjectTemplateBuilder& SetProperty(const base::StringPiece& name,
const T& getter, const U& setter) {
return SetPropertyImpl(name,
CallbackTraits<T>::CreateTemplate(isolate_, getter),
CallbackTraits<U>::CreateTemplate(isolate_, setter));
}
v8::Local<v8::ObjectTemplate> Build();
private:
ObjectTemplateBuilder& SetImpl(const base::StringPiece& name,
v8::Handle<v8::Data> val);
ObjectTemplateBuilder& SetPropertyImpl(
const base::StringPiece& name, v8::Handle<v8::FunctionTemplate> getter,
v8::Handle<v8::FunctionTemplate> setter);
v8::Isolate* isolate_;
// ObjectTemplateBuilder should only be used on the stack.
v8::Local<v8::ObjectTemplate> template_;
};
} // namespace mate
#endif // NATIVE_MATE_OBJECT_TEMPLATE_BUILDER_H_