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

/*
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#ifndef DeviceOrientationDispatcher_h
#define DeviceOrientationDispatcher_h

#include "base/memory/scoped_refptr.h"
#include "core/frame/PlatformEventDispatcher.h"
#include "platform/heap/Handle.h"
#include "public/platform/WebPlatformEventType.h"
#include "public/platform/modules/device_orientation/WebDeviceOrientationListener.h"

namespace device {
class OrientationData;
}

namespace blink {

class DeviceOrientationData;

// This class listens to device orientation data and notifies all registered
// controllers.
class DeviceOrientationDispatcher final
    : public GarbageCollectedFinalized<DeviceOrientationDispatcher>,
      public PlatformEventDispatcher,
      public WebDeviceOrientationListener {
  USING_GARBAGE_COLLECTED_MIXIN(DeviceOrientationDispatcher);

 public:
  static DeviceOrientationDispatcher& Instance(bool absolute);
  ~DeviceOrientationDispatcher() override;

  // 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.
  void DidChangeDeviceOrientation(const device::OrientationData&) override;

  virtual void Trace(blink::Visitor*);

 private:
  explicit DeviceOrientationDispatcher(bool absolute);

  // Inherited from PlatformEventDispatcher.
  void StartListening() override;
  void StopListening() override;

  WebPlatformEventType GetWebPlatformEventType() const;

  const bool absolute_;
  Member<DeviceOrientationData> last_device_orientation_data_;
};

}  // namespace blink

#endif  // DeviceOrientationDispatcher_h