Source/modules/device_orientation/DeviceMotionDispatcher.h

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef DeviceMotionDispatcher_h
#define DeviceMotionDispatcher_h

#include "DeviceMotionData.h"
#include "wtf/RefPtr.h"
#include "wtf/Vector.h"
#include "public/platform/WebDeviceMotionListener.h"

namespace WebKit {
class WebDeviceMotionData;
}

namespace WebCore {

class DeviceMotionController;
class DeviceMotionData;

// This class listens to device motion data and dispatches it to all
// listening controllers.
class DeviceMotionDispatcher : public WebKit::WebDeviceMotionListener {
public:
    static DeviceMotionDispatcher& instance();

    void addController(DeviceMotionController*);
    void removeController(DeviceMotionController*);

    // Note that the returned object is owned by this class.
    // FIXME: make the return value const, see crbug.com/233174.
    DeviceMotionData* latestDeviceMotionData();

    // This method is called every time new device motion data is available.
    virtual void didChangeDeviceMotion(const WebKit::WebDeviceMotionData&) OVERRIDE;

private:
    DeviceMotionDispatcher();
    ~DeviceMotionDispatcher();

    void startListening();
    void stopListening();

    void purgeControllers();

    RefPtr<DeviceMotionData> m_lastDeviceMotionData;
    Vector<DeviceMotionController*> m_controllers;
};

} // namespace WebCore

#endif // DeviceMotionDispatcher_h