geolocation_provider.h revision b2df76ea8fec9e32f6f3718986dba0d95315b29c 
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_PUBLIC_BROWSER_GEOLOCATION_PROVIDER_H_
6#define CONTENT_PUBLIC_BROWSER_GEOLOCATION_PROVIDER_H_
7
8#include "base/callback_forward.h"
9#include "content/common/content_export.h"
10
11namespace content {
12struct Geoposition;
13
14class CONTENT_EXPORT GeolocationProvider {
15 public:
16  // This method, and all below, can only be called on the IO thread unless
17  // otherwise specified.
18  static GeolocationProvider* GetInstance();
19
20  typedef base::Callback<void(const Geoposition&)> LocationUpdateCallback;
21
22  // |use_high_accuracy| is used as a 'hint' for the provider preferences for
23  // this particular observer, however the observer could receive updates for
24  // best available locations from any active provider whilst it is registered.
25  // If an existing observer is added a second time, its options are updated
26  // but only a single call to RemoveLocationUpdateCallback() is required to
27  // remove it.
28  virtual void AddLocationUpdateCallback(const LocationUpdateCallback& callback,
29                                         bool use_high_accuracy) = 0;
30
31  // Remove a previously registered observer. No-op if not previously registered
32  // via AddLocationUpdateCallback(). Returns true if the observer was removed.
33  virtual bool RemoveLocationUpdateCallback(
34      const LocationUpdateCallback& callback) = 0;
35
36  // Calling this method indicates the user has opted into using location
37  // services, including sending network requests to [Google servers to] resolve
38  // the user's location. Use this method carefully, in line with the rules in
39  // go/chrome-privacy-doc.
40  virtual void UserDidOptIntoLocationServices() = 0;
41
42  // Overrides the current location for testing. This function may be called on
43  // any thread. The completion callback will be invoked asynchronously on the
44  // calling thread when the override operation is completed.
45  //
46  // This function allows the current location to be faked without having to
47  // manually instantiate a GeolocationProvider backed by a MockLocationProvider
48  // that serves a fake location.
49  //
50  // Do not use this function in unit tests. The function instantiates the
51  // singleton geolocation stack in the background and manipulates it to report
52  // a fake location. Neither step can be undone, breaking unit test isolation
53  // (crbug.com/125931).
54  static void OverrideLocationForTesting(
55      const Geoposition& position,
56      const base::Closure& completion_callback);
57
58 protected:
59  virtual~GeolocationProvider() {}
60};
61
62}  // namespace content
63
64#endif  // CONTENT_PUBLIC_BROWSER_GEOLOCATION_PROVIDER_H_
65