ash/accelerators/accelerator_controller.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 ASH_ACCELERATORS_ACCELERATOR_CONTROLLER_H_
   6 #define ASH_ACCELERATORS_ACCELERATOR_CONTROLLER_H_
   7
   8 #include <map>
   9 #include <set>
  10
  11 #include "ash/accelerators/exit_warning_handler.h"
  12 #include "ash/ash_export.h"
  13 #include "base/basictypes.h"
  14 #include "base/compiler_specific.h"
  15 #include "base/gtest_prod_util.h"
  16 #include "base/memory/scoped_ptr.h"
  17 #include "ui/base/accelerators/accelerator.h"
  18
  19 namespace ui {
  20 class AcceleratorManager;
  21 }
  22
  23 namespace ash {
  24
  25 struct AcceleratorData;
  26 class BrightnessControlDelegate;
  27 class ExitWarningHandler;
  28 class ImeControlDelegate;
  29 class KeyboardBrightnessControlDelegate;
  30 class ScreenshotDelegate;
  31 class VolumeControlDelegate;
  32
  33 // AcceleratorController provides functions for registering or unregistering
  34 // global keyboard accelerators, which are handled earlier than any windows. It
  35 // also implements several handlers as an accelerator target.
  36 class ASH_EXPORT AcceleratorController : public ui::AcceleratorTarget {
  37  public:
  38   AcceleratorController();
  39   virtual ~AcceleratorController();
  40
  41   // A list of possible ways in which an accelerator should be restricted before
  42   // processing. Any target registered with this controller should respect
  43   // restrictions by calling |GetCurrentAcceleratorRestriction| during
  44   // processing.
  45   enum AcceleratorProcessingRestriction {
  46     // Process the accelerator normally.
  47     RESTRICTION_NONE,
  48
  49     // Don't process the accelerator.
  50     RESTRICTION_PREVENT_PROCESSING,
  51
  52     // Don't process the accelerator and prevent propagation to other targets.
  53     RESTRICTION_PREVENT_PROCESSING_AND_PROPAGATION
  54   };
  55
  56   // Registers a global keyboard accelerator for the specified target. If
  57   // multiple targets are registered for an accelerator, a target registered
  58   // later has higher priority.
  59   void Register(const ui::Accelerator& accelerator,
  60                 ui::AcceleratorTarget* target);
  61
  62   // Unregisters the specified keyboard accelerator for the specified target.
  63   void Unregister(const ui::Accelerator& accelerator,
  64                   ui::AcceleratorTarget* target);
  65
  66   // Unregisters all keyboard accelerators for the specified target.
  67   void UnregisterAll(ui::AcceleratorTarget* target);
  68
  69   // Activates the target associated with the specified accelerator.
  70   // First, AcceleratorPressed handler of the most recently registered target
  71   // is called, and if that handler processes the event (i.e. returns true),
  72   // this method immediately returns. If not, we do the same thing on the next
  73   // target, and so on.
  74   // Returns true if an accelerator was activated.
  75   bool Process(const ui::Accelerator& accelerator);
  76
  77   // Returns true if the |accelerator| is registered.
  78   bool IsRegistered(const ui::Accelerator& accelerator) const;
  79
  80   // Returns true if the |accelerator| is one of the |reserved_actions_|.
  81   bool IsReservedAccelerator(const ui::Accelerator& accelerator) const;
  82
  83   // Performs the specified action. The |accelerator| may provide additional
  84   // data the action needs. Returns whether an action was performed
  85   // successfully.
  86   bool PerformAction(int action,
  87                      const ui::Accelerator& accelerator);
  88
  89   // Returns the restriction for the current context.
  90   AcceleratorProcessingRestriction GetCurrentAcceleratorRestriction();
  91
  92   // Overridden from ui::AcceleratorTarget:
  93   virtual bool AcceleratorPressed(const ui::Accelerator& accelerator) OVERRIDE;
  94   virtual bool CanHandleAccelerators() const OVERRIDE;
  95
  96   void SetBrightnessControlDelegate(
  97       scoped_ptr<BrightnessControlDelegate> brightness_control_delegate);
  98   void SetImeControlDelegate(
  99       scoped_ptr<ImeControlDelegate> ime_control_delegate);
 100   void SetScreenshotDelegate(
 101       scoped_ptr<ScreenshotDelegate> screenshot_delegate);
 102   BrightnessControlDelegate* brightness_control_delegate() const {
 103     return brightness_control_delegate_.get();
 104   }
 105   ScreenshotDelegate* screenshot_delegate() {
 106     return screenshot_delegate_.get();
 107   }
 108
 109   // Provides access to the ExitWarningHandler for testing.
 110   ExitWarningHandler* GetExitWarningHandlerForTest() {
 111     return &exit_warning_handler_;
 112   }
 113
 114   const ui::Accelerator& previous_accelerator_for_test() const {
 115     return previous_accelerator_;
 116   }
 117
 118  private:
 119   FRIEND_TEST_ALL_PREFIXES(AcceleratorControllerTest, GlobalAccelerators);
 120   FRIEND_TEST_ALL_PREFIXES(AcceleratorControllerTest,
 121                            DontRepeatToggleFullscreen);
 122
 123   // Initializes the accelerators this class handles as a target.
 124   void Init();
 125
 126   // Registers the specified accelerators.
 127   void RegisterAccelerators(const AcceleratorData accelerators[],
 128                             size_t accelerators_length);
 129
 130   // Get the accelerator restriction for the given action. Supply an |action|
 131   // of -1 to get restrictions that apply for the current context.
 132   AcceleratorProcessingRestriction GetAcceleratorProcessingRestriction(
 133       int action);
 134
 135   void SetKeyboardBrightnessControlDelegate(
 136       scoped_ptr<KeyboardBrightnessControlDelegate>
 137       keyboard_brightness_control_delegate);
 138
 139   scoped_ptr<ui::AcceleratorManager> accelerator_manager_;
 140
 141   // TODO(derat): BrightnessControlDelegate is also used by the system tray;
 142   // move it outside of this class.
 143   scoped_ptr<BrightnessControlDelegate> brightness_control_delegate_;
 144   scoped_ptr<ImeControlDelegate> ime_control_delegate_;
 145   scoped_ptr<KeyboardBrightnessControlDelegate>
 146       keyboard_brightness_control_delegate_;
 147   scoped_ptr<ScreenshotDelegate> screenshot_delegate_;
 148
 149   // Remember previous accelerator as some accelerator needs to be fired
 150   // with a specific sequence.
 151   ui::Accelerator previous_accelerator_;
 152
 153   // Handles the exit accelerator which requires a double press to exit and
 154   // shows a popup with an explanation.
 155   ExitWarningHandler exit_warning_handler_;
 156
 157   // A map from accelerators to the AcceleratorAction values, which are used in
 158   // the implementation.
 159   std::map<ui::Accelerator, int> accelerators_;
 160
 161   // Actions allowed when the user is not signed in.
 162   std::set<int> actions_allowed_at_login_screen_;
 163   // Actions allowed when the screen is locked.
 164   std::set<int> actions_allowed_at_lock_screen_;
 165   // Actions allowed when a modal window is up.
 166   std::set<int> actions_allowed_at_modal_window_;
 167   // Reserved actions. See accelerator_table.h for details.
 168   std::set<int> reserved_actions_;
 169   // Actions which will not be repeated while holding the accelerator key.
 170   std::set<int> nonrepeatable_actions_;
 171   // Actions allowed in app mode.
 172   std::set<int> actions_allowed_in_app_mode_;
 173   // Actions disallowed if there are no windows.
 174   std::set<int> actions_needing_window_;
 175
 176   DISALLOW_COPY_AND_ASSIGN(AcceleratorController);
 177 };
 178
 179 }  // namespace ash
 180
 181 #endif  // ASH_ACCELERATORS_ACCELERATOR_CONTROLLER_H_