third_party/WebKit/Source/modules/device_orientation/DeviceOrientationDispatcher.h

/*
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#ifndef DeviceOrientationDispatcher_h
#define DeviceOrientationDispatcher_h

#include "core/frame/PlatformEventDispatcher.h"
#include "platform/heap/Handle.h"
#include "public/platform/WebDeviceOrientationListener.h"
#include "wtf/RefPtr.h"

namespace blink {

class DeviceOrientationController;
class DeviceOrientationData;
class WebDeviceOrientationData;

// This class listens to device orientation data and notifies all registered controllers.
class DeviceOrientationDispatcher : public PlatformEventDispatcher, public WebDeviceOrientationListener {
public:
    static DeviceOrientationDispatcher& instance();

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

    // Inherited from WebDeviceOrientationListener.
    virtual void didChangeDeviceOrientation(const WebDeviceOrientationData&) OVERRIDE;

private:
    DeviceOrientationDispatcher();
    ~DeviceOrientationDispatcher();

    // Inherited from PlatformEventDispatcher.
    virtual void startListening() OVERRIDE;
    virtual void stopListening() OVERRIDE;

    Persistent<DeviceOrientationData> m_lastDeviceOrientationData;
};

} // namespace blink

#endif // DeviceOrientationDispatcher_h