Create network change notifier.

webrtc/base/networkchangenotifier.h

+/*
+ *  Copyright 2015 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_BASE_NETWORKCHANGENOTIFIER_H_
+#define WEBRTC_BASE_NETWORKCHANGENOTIFIER_H_
+
+#include "webrtc/base/logging.h"
+#include "webrtc/base/scoped_ptr.h"
+#include "webrtc/base/sigslot.h"
+
+namespace rtc {
+class NetworkChangeNotifier;
+class NetworkChangeNotifierDelegate;
+
+/*
+ * NetworkChangeNotifierFactory creates a notifier and a delegate.
+ * The delegate receives the network change notification from the
+ * external source (e.g., OS events) and passes it down to the notifier.
+ */
+class NetworkChangeNotifierFactory {
+ public:
+  static NetworkChangeNotifierFactory* CreateFactory();
+
+  NetworkChangeNotifierDelegate* CreateDelegate();
+  NetworkChangeNotifierDelegate* GetDelegate();
+
+  NetworkChangeNotifier* CreateNotifier();
+
+ private:
+  NetworkChangeNotifierFactory() {}
+  scoped_ptr<NetworkChangeNotifierDelegate> delegate_;
+};
+
+/*
+ * The purpose of the delegate is to separate the class receiving the
+ * notification from the one notifying the NetworkManager.
+ */
+class NetworkChangeNotifierDelegate {
+ public:
+  // Signal to be fired when it was notified network changes.
+  sigslot::signal0<> SignalNetworksChanged;
+
+  NetworkChangeNotifierDelegate() {}
+
+  // Called when it was notified about network changes.
+  void OnNetworkChangeNotified();
+};
+
+class NetworkChangeNotifier : public sigslot::has_slots<> {
+ public:
+  static void SetFactory(NetworkChangeNotifierFactory* factory);
+  static NetworkChangeNotifierFactory* GetFactory();
+  sigslot::signal0<> SignalNetworksChanged;
+
+  explicit NetworkChangeNotifier(NetworkChangeNotifierDelegate* delegate);
+
+ private:
+  // Called when it was notified about network changes by the delegate.
+  void OnNetworkChangeNotified() {
+    SignalNetworksChanged();
+  }
+
+  NetworkChangeNotifierDelegate* delegate_;
+};

[pthatcher1, 2015/10/09 23:11:29]

This seems really complex.  Let's try and simplify it.

[honghaiz3, 2015/10/13 23:19:56]

Done.

+
+}  // namespace rtc
+
+#endif  // WEBRTC_BASE_NETWORKCHANGENOTIFIER_H_