Battery Status API: browser-side implementation.

content/browser/battery_status/battery_status_service.h

+// Copyright 2014 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 file.
+
+#ifndef CONTENT_BROWSER_BATTERY_STATUS_BATTERY_STATUS_SERVICE_H_
+#define CONTENT_BROWSER_BATTERY_STATUS_BATTERY_STATUS_SERVICE_H_
+
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/singleton.h"
+#include "content/browser/battery_status/battery_status_update_callback.h"
+#include "content/common/content_export.h"
+#include "third_party/WebKit/public/platform/WebBatteryStatus.h"
+
+namespace content {
+class BatteryStatusManagerInterface;
+
+class CONTENT_EXPORT BatteryStatusService {
+ public:
+  // Returns the BatteryStatusService singleton.
+  static BatteryStatusService* GetInstance();
+
+  // Adds a callback to receive battery status updates.
+  // Must be called on the I/O thread.
+  void AddCallback(const BatteryStatusUpdateCallback& callback);

[jochen (gone - plz use gerrit), 2014/05/19 13:14:22]

can you move BatteryStatusUpdateCallback's definition to a class? It shouldn't
be in the content namespace and doesn't warrant its own header.

[timvolodine, 2014/05/22 10:02:33]

done. I've put it inside this class.

+
+  // Removes a callback. Must be called on the I/O thread.
+  void RemoveCallback(const BatteryStatusUpdateCallback& callback);
+
+  // Gracefully clean-up.
+  void Shutdown();
+
+  // Injects a custom battery status manager for testing purposes.
+  // This class takes ownership of the injected object.
+  void SetBatteryManagerForTests(

[jochen (gone - plz use gerrit), 2014/05/19 13:14:22]

ForTesting instead of ForTests

[timvolodine, 2014/05/22 10:02:33]

Done.

+      BatteryStatusManagerInterface* test_battery_manager);
+
+  // Returns callback to invoke when battery is changed. Used for testing.
+  const BatteryStatusUpdateCallback& update_callback() const;

[jochen (gone - plz use gerrit), 2014/05/19 13:14:22]

GetUpdateCallbackForTesting

[timvolodine, 2014/05/22 10:02:33]

Done.

+
+ private:
+  friend struct DefaultSingletonTraits<BatteryStatusService>;
+
+  BatteryStatusService();
+  virtual ~BatteryStatusService();
+
+  // Updates current battery status and sends new status to interested
+  // render processes. Can be called on any thread via a callback.
+  void UpdateBatteryStatus(const blink::WebBatteryStatus& status);
+  void NotifyConsumers(const blink::WebBatteryStatus& status);
+
+  scoped_ptr<BatteryStatusManagerInterface> battery_fetcher_;
+  std::vector<BatteryStatusUpdateCallback> callbacks_;

[Michael van Ouwerkerk, 2014/05/19 11:19:22]

Looks like base::CallbackList would be suitable here.

[jochen (gone - plz use gerrit), 2014/05/19 13:14:22]

+1

[timvolodine, 2014/05/22 10:02:33]

Done.

[timvolodine, 2014/05/22 10:02:33]

Done.

+  blink::WebBatteryStatus status_;
+  BatteryStatusUpdateCallback update_callback_;
+  bool status_updated_;
+  bool is_shutdown_;
+
+  DISALLOW_COPY_AND_ASSIGN(BatteryStatusService);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_BATTERY_STATUS_BATTERY_STATUS_SERVICE_H_