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_weak_ref.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/synchronization/lock.h"
  13
  14 namespace base {
  15 class SingleThreadTaskRunner;
  16 }
  17
  18 namespace content {
  19 class LocationProviderAndroid;
  20 struct Geoposition;
  21
  22 // Interacts with JNI and reports back to AndroidLocationProvider.
  23 // This class creates a LocationProvider java object and listens for
  24 // updates.
  25 // The simplified flow is:
  26 // GeolocationProvider runs in a Geolocation Thread and fetches geolocation data
  27 // from a LocationProvider.
  28 // AndroidLocationProvider access a singleton AndroidLocationApiAdapter
  29 // AndroidLocationApiAdapter calls via JNI and uses the main thread Looper
  30 // in the java side to listen for location updates. We then bounce these updates
  31 // to the Geolocation thread.
  32 // Note that AndroidLocationApiAdapter is a singleton and there's at most only
  33 // one AndroidLocationProvider that has called Start().
  34 class AndroidLocationApiAdapter {
  35  public:
  36   // Starts the underlying location provider, returns true if successful.
  37   // Called on the Geolocation thread.
  38   bool Start(LocationProviderAndroid* location_provider, bool high_accuracy);
  39   // Stops the underlying location provider.
  40   // Called on the Geolocation thread.
  41   void Stop();
  42
  43   // Returns our singleton.
  44   static AndroidLocationApiAdapter* GetInstance();
  45
  46   // Called when initializing chrome_view to obtain a pointer to the java class.
  47   static bool RegisterGeolocationService(JNIEnv* env);
  48
  49   // Called by JNI on main thread looper.
  50   static void OnNewLocationAvailable(double latitude,
  51                                      double longitude,
  52                                      double time_stamp,
  53                                      bool has_altitude, double altitude,
  54                                      bool has_accuracy, double accuracy,
  55                                      bool has_heading, double heading,
  56                                      bool has_speed, double speed);
  57   static void OnNewErrorAvailable(JNIEnv* env, jstring message);
  58
  59  private:
  60   friend struct base::DefaultSingletonTraits<AndroidLocationApiAdapter>;
  61   AndroidLocationApiAdapter();
  62   ~AndroidLocationApiAdapter();
  63
  64   void CreateJavaObject(JNIEnv* env);
  65
  66   // Called on the JNI main thread looper.
  67   void OnNewGeopositionInternal(const Geoposition& geoposition);
  68
  69   /// Called on the Geolocation thread.
  70   static void NotifyProviderNewGeoposition(const Geoposition& geoposition);
  71
  72   base::android::ScopedJavaGlobalRef<jobject>
  73       java_location_provider_android_object_;
  74   LocationProviderAndroid* location_provider_;
  75
  76   // Guards against the following member which is accessed on Geolocation
  77   // thread and the JNI main thread looper.
  78   base::Lock lock_;
  79   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
  80 };
  81
  82 }  // namespace content
  83
  84 #endif  // CONTENT_BROWSER_GEOLOCATION_LOCATION_API_ADAPTER_ANDROID_H_