blob: dea3c7ee3f428ad2ca204a131b90fb12ba80b915 [file] [log] [blame]
// Copyright (c) 2012 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 "base/callback_list.h"
#include "content/common/content_export.h"
namespace content {
struct Geoposition;
// This is the main API to the geolocation subsystem. The application will hold
// a single instance of this class and can register multiple clients to be
// notified of location changes:
// * Callbacks are registered by AddLocationUpdateCallback() and will keep
// receiving updates until the returned subscription object is destructed.
// The application must instantiate the GeolocationProvider on the UI thread and
// must communicate with it on the same thread.
// The underlying location arbitrator will only be enabled whilst there is at
// least one registered observer or pending callback (and only after
// UserDidOptIntoLocationServices). The arbitrator and the location providers it
// uses run on a separate Geolocation thread.
class GeolocationProvider {
CONTENT_EXPORT static GeolocationProvider* GetInstance();
typedef base::Callback<void(const Geoposition&)> LocationUpdateCallback;
typedef base::CallbackList<void(const Geoposition&)>::Subscription
// |use_high_accuracy| is used as a 'hint' for the provider preferences for
// this particular observer, however the observer could receive updates for
// best available locations from any active provider whilst it is registered.
virtual scoped_ptr<Subscription> AddLocationUpdateCallback(
const LocationUpdateCallback& callback, bool use_high_accuracy) = 0;
// Calling this method indicates the user has opted into using location
// services, including sending network requests to [Google servers to] resolve
// the user's location. Use this method carefully, in line with the rules in
// go/chrome-privacy-doc.
virtual void UserDidOptIntoLocationServices() = 0;
// Overrides the current location for testing.
// Overrides the location for automation/testing. Suppresses any further
// updates from the actual providers and sends an update with the overridden
// position to all registered clients.
// Do not use this function in unit tests. The function instantiates the
// singleton geolocation stack in the background and manipulates it to report
// a fake location. Neither step can be undone, breaking unit test isolation
// (
virtual void OverrideLocationForTesting(const Geoposition& position) = 0;
virtual~GeolocationProvider() {}
} // namespace content