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 UI_BASE_ACCELERATORS_ACCELERATOR_MANAGER_H_ 6 #define UI_BASE_ACCELERATORS_ACCELERATOR_MANAGER_H_ 7 8 #include <list> 9 #include <map> 10 #include <utility> 11 12 #include "base/basictypes.h" 13 #include "ui/base/accelerators/accelerator.h" 14 #include "ui/base/ui_export.h" 15 #include "ui/events/event_constants.h" 16 17 namespace ui { 18 19 // The AcceleratorManger is used to handle keyboard accelerators. 20 class UI_EXPORT AcceleratorManager { 21 public: 22 enum HandlerPriority { 23 kNormalPriority, 24 kHighPriority, 25 }; 26 27 AcceleratorManager(); 28 ~AcceleratorManager(); 29 30 // Register a keyboard accelerator for the specified target. If multiple 31 // targets are registered for an accelerator, a target registered later has 32 // higher priority. 33 // |accelerator| is the accelerator to register. 34 // |priority| denotes the priority of the handler. 35 // NOTE: In almost all cases, you should specify kNormalPriority for this 36 // parameter. Setting it to kHighPriority prevents Chrome from sending the 37 // shortcut to the webpage if the renderer has focus, which is not desirable 38 // except for very isolated cases. 39 // |target| is the AcceleratorTarget that handles the event once the 40 // accelerator is pressed. 41 // Note that we are currently limited to accelerators that are either: 42 // - a key combination including Ctrl or Alt 43 // - the escape key 44 // - the enter key 45 // - any F key (F1, F2, F3 ...) 46 // - any browser specific keys (as available on special keyboards) 47 void Register(const Accelerator& accelerator, 48 HandlerPriority priority, 49 AcceleratorTarget* target); 50 51 // Unregister the specified keyboard accelerator for the specified target. 52 void Unregister(const Accelerator& accelerator, AcceleratorTarget* target); 53 54 // Unregister all keyboard accelerator for the specified target. 55 void UnregisterAll(AcceleratorTarget* target); 56 57 // Activate the target associated with the specified accelerator. 58 // First, AcceleratorPressed handler of the most recently registered target 59 // is called, and if that handler processes the event (i.e. returns true), 60 // this method immediately returns. If not, we do the same thing on the next 61 // target, and so on. 62 // Returns true if an accelerator was activated. 63 bool Process(const Accelerator& accelerator); 64 65 // Returns the AcceleratorTarget that should be activated for the specified 66 // keyboard accelerator, or NULL if no view is registered for that keyboard 67 // accelerator. 68 AcceleratorTarget* GetCurrentTarget(const Accelerator& accelertor) const; 69 70 // Whether the given |accelerator| has a priority handler associated with it. 71 bool HasPriorityHandler(const Accelerator& accelerator) const; 72 73 private: 74 // The accelerators and associated targets. 75 typedef std::list<AcceleratorTarget*> AcceleratorTargetList; 76 // This construct pairs together a |bool| (denoting whether the list contains 77 // a priority_handler at the front) with the list of AcceleratorTargets. 78 typedef std::pair<bool, AcceleratorTargetList> AcceleratorTargets; 79 typedef std::map<Accelerator, AcceleratorTargets> AcceleratorMap; 80 AcceleratorMap accelerators_; 81 82 DISALLOW_COPY_AND_ASSIGN(AcceleratorManager); 83 }; 84 85 } // namespace ui 86 87 #endif // UI_BASE_ACCELERATORS_ACCELERATOR_MANAGER_H_ 88