Generic Sensor API : Ambient Light Sensor API.

third_party/WebKit/Source/modules/sensor/AmbientLightSensorDispatcher.cpp

+// Copyright 2016 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.
+
+#include "modules/sensor/AmbientLightSensorDispatcher.h"
+
+#include "platform/mojo/MojoHelper.h"
+#include "public/platform/Platform.h"
+#include "public/platform/ServiceRegistry.h"
+#include "wtf/PassOwnPtr.h"
+
+namespace blink {
+
+AmbientLightSensorDispatcher& AmbientLightSensorDispatcher::instance()
+{
+    DEFINE_STATIC_LOCAL(Persistent<AmbientLightSensorDispatcher>, lightSensorDispatcher, (new AmbientLightSensorDispatcher()));
+    return *lightSensorDispatcher;
+}
+
+AmbientLightSensorDispatcher::AmbientLightSensorDispatcher()
+    : m_hasLatestData(false)
+{
+}
+
+void AmbientLightSensorDispatcher::queryNextReading()
+{
+    m_lightSensor->QueryNextReading(createBaseCallback(bind<device::blink::AmbientLightSensorReadingPtr>(&AmbientLightSensorDispatcher::onDidChange, this)));
+}
+
+void AmbientLightSensorDispatcher::startReading()
+{
+    m_lightSensor->StartReading();
+}
+
+void AmbientLightSensorDispatcher::stopReading()
+{
+    m_lightSensor->StopReading();
+}
+
+void AmbientLightSensorDispatcher::onDidChange(device::blink::AmbientLightSensorReadingPtr alsReading)
+{
+    queryNextReading();
+
+    DCHECK(alsReading);
+
+    updateSensorReading(AmbientLightSensorReadingProxy(
+        alsReading->timeStamp, alsReading->illuminance));
+}
+
+void AmbientLightSensorDispatcher::updateSensorReading(const AmbientLightSensorReadingProxy& alsReading)
+{
+    m_alsReading = alsReading;
+    m_hasLatestData = true;
+    notifyControllers();
+}
+
+void AmbientLightSensorDispatcher::startListening()
+{
+    DCHECK(!m_lightSensor.is_bound());
+    Platform::current()->serviceRegistry()->connectToRemoteService(mojo::GetProxy(&m_lightSensor));
+    if (!m_hasLatestData)
+        startReading();
+
+    queryNextReading();
+}
+
+void AmbientLightSensorDispatcher::stopListening()
+{
+    stopReading();
+    m_lightSensor.reset();
+    m_hasLatestData = false;
+}
+
+} // namespace blink