athena/system/orientation_controller.h

   1 // Copyright 2014 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 ATHENA_SYSTEM_ORIENTATION_CONTROLLER_H_
   6 #define ATHENA_SYSTEM_ORIENTATION_CONTROLLER_H_
   7
   8 #include "athena/system/device_socket_listener.h"
   9 #include "base/macros.h"
  10 #include "base/memory/ref_counted.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/memory/weak_ptr.h"
  13 #include "ui/gfx/display.h"
  14
  15 namespace base {
  16 class FilePath;
  17 class FilePathWatcher;
  18 class TaskRunner;
  19 }
  20
  21 namespace athena {
  22
  23 // Monitors accelerometers, detecting orientation changes. When a change is
  24 // detected rotates the root window to match.
  25 class OrientationController
  26     : public DeviceSocketListener,
  27       public base::RefCountedThreadSafe<OrientationController> {
  28  public:
  29   OrientationController();
  30
  31   void InitWith(scoped_refptr<base::TaskRunner> file_task_runner);
  32
  33   void Shutdown();
  34
  35  private:
  36   friend class base::RefCountedThreadSafe<OrientationController>;
  37
  38   virtual ~OrientationController();
  39
  40   void ShutdownOnFILE();
  41   // Watch for the socket path to be created, called on the FILE thread.
  42   void WatchForSocketPathOnFILE();
  43   void OnFilePathChangedOnFILE(const base::FilePath& path, bool error);
  44
  45   // Overridden from device::DeviceSocketListener:
  46   virtual void OnDataAvailableOnFILE(const void* data) OVERRIDE;
  47
  48   // Rotates the display to |rotation|, called on the UI thread.
  49   void RotateOnUI(gfx::Display::Rotation rotation);
  50
  51   // The last configured rotation.
  52   gfx::Display::Rotation current_rotation_;
  53
  54   // The timestamp of the last applied orientation change.
  55   int64_t last_orientation_change_time_;
  56
  57   // True if the OrientaionController has already been shutdown.
  58   // This is initialized on UI thread, but must be accessed / modified
  59   // only on FILE thread.
  60   bool shutdown_;
  61
  62   // A task runner for the UI thread.
  63   scoped_refptr<base::TaskRunner> ui_task_runner_;
  64
  65   // A task runner for the FILE thread.
  66   scoped_refptr<base::TaskRunner> file_task_runner_;
  67
  68   // File path watcher used to detect when sensors are present.
  69   scoped_ptr<base::FilePathWatcher> watcher_;
  70
  71   DISALLOW_COPY_AND_ASSIGN(OrientationController);
  72 };
  73
  74 }  // namespace athena
  75
  76 #endif  // ATHENA_SYSTEM_ORIENTATION_CONTROLLER_H_