lazy_interface_ptr.h revision 116680a4aac90f2aa7413d9095a592090648e557 
1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef MOJO_PUBLIC_CPP_APPLICATION_LAZY_INTERFACE_PTR_H_
6#define MOJO_PUBLIC_CPP_APPLICATION_LAZY_INTERFACE_PTR_H_
7
8#include <string>
9
10#include "mojo/public/cpp/application/connect.h"
11#include "mojo/public/interfaces/service_provider/service_provider.mojom.h"
12
13namespace mojo {
14
15template<typename Interface>
16class LazyInterfacePtr : InterfacePtr<Interface> {
17 public:
18  LazyInterfacePtr(ServiceProvider* service_provider)
19      : service_provider_(service_provider) {
20  }
21
22  Interface* get() const {
23    if (!InterfacePtr<Interface>::get()) {
24      mojo::ConnectToService<Interface>(
25          service_provider_,
26          const_cast<LazyInterfacePtr<Interface>*>(this));
27    }
28    return InterfacePtr<Interface>::get();
29  }
30  Interface* operator->() const { return get(); }
31  Interface& operator*() const { return *get(); }
32
33 private:
34  ServiceProvider* service_provider_;
35};
36
37}  // namespace mojo
38
39#endif  // MOJO_PUBLIC_CPP_APPLICATION_LAZY_INTERFACE_PTR_H_
40