content/browser/geolocation/location_api_adapter_android.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_GEOLOCATION_LOCATION_API_ADAPTER_ANDROID_H_
   6 #define CONTENT_BROWSER_GEOLOCATION_LOCATION_API_ADAPTER_ANDROID_H_
   7
   8 #include "base/android/jni_helper.h"
   9 #include "base/android/scoped_java_ref.h"
  10 #include "base/memory/ref_counted.h"
  11 #include "base/memory/singleton.h"
  12 #include "base/message_loop/message_loop_proxy.h"
  13 #include "base/synchronization/lock.h"
  14
  15 namespace content {
  16 class LocationProviderAndroid;
  17 struct Geoposition;
  18
  19 // Interacts with JNI and reports back to AndroidLocationProvider.
  20 // This class creates a LocationProvider java object and listens for
  21 // updates.
  22 // The simplified flow is:
  23 // GeolocationProvider runs in a Geolocation Thread and fetches geolocation data
  24 // from a LocationProvider.
  25 // AndroidLocationProvider access a singleton AndroidLocationApiAdapter
  26 // AndroidLocationApiAdapter calls via JNI and uses the main thread Looper
  27 // in the java side to listen for location updates. We then bounce these updates
  28 // to the Geolocation thread.
  29 // Note that AndroidLocationApiAdapter is a singleton and there's at most only
  30 // one AndroidLocationProvider that has called Start().
  31 class AndroidLocationApiAdapter {
  32  public:
  33   // Starts the underlying location provider, returns true if successful.
  34   // Called on the Geolocation thread.
  35   bool Start(LocationProviderAndroid* location_provider, bool high_accuracy);
  36   // Stops the underlying location provider.
  37   // Called on the Geolocation thread.
  38   void Stop();
  39
  40   // Returns our singleton.
  41   static AndroidLocationApiAdapter* GetInstance();
  42
  43   // Called when initializing chrome_view to obtain a pointer to the java class.
  44   static bool RegisterGeolocationService(JNIEnv* env);
  45
  46   // Called by JNI on main thread looper.
  47   static void OnNewLocationAvailable(double latitude,
  48                                      double longitude,
  49                                      double time_stamp,
  50                                      bool has_altitude, double altitude,
  51                                      bool has_accuracy, double accuracy,
  52                                      bool has_heading, double heading,
  53                                      bool has_speed, double speed);
  54   static void OnNewErrorAvailable(JNIEnv* env, jstring message);
  55
  56  private:
  57   friend struct DefaultSingletonTraits<AndroidLocationApiAdapter>;
  58   AndroidLocationApiAdapter();
  59   ~AndroidLocationApiAdapter();
  60
  61   void CreateJavaObject(JNIEnv* env);
  62
  63   // Called on the JNI main thread looper.
  64   void OnNewGeopositionInternal(const Geoposition& geoposition);
  65
  66   /// Called on the Geolocation thread.
  67   static void NotifyProviderNewGeoposition(const Geoposition& geoposition);
  68
  69   base::android::ScopedJavaGlobalRef<jobject>
  70       java_location_provider_android_object_;
  71   LocationProviderAndroid* location_provider_;
  72
  73   // Guards against the following member which is accessed on Geolocation
  74   // thread and the JNI main thread looper.
  75   base::Lock lock_;
  76   scoped_refptr<base::MessageLoopProxy> message_loop_;
  77 };
  78
  79 }  // namespace content
  80
  81 #endif  // CONTENT_BROWSER_GEOLOCATION_LOCATION_API_ADAPTER_ANDROID_H_