Mac global keybindings

chrome/browser/extensions/global_shortcut_listener_mac.h

 // Copyright (c) 2013 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_GLOBAL_SHORTCUT_LISTENER_MAC_H_
 #define CHROME_BROWSER_EXTENSIONS_GLOBAL_SHORTCUT_LISTENER_MAC_H_
 
+#include "chrome/browser/extensions/global_shortcut_listener.h"
+
+#include <Carbon/Carbon.h>
+#include <CoreFoundation/CoreFoundation.h>
+
+#include <map>
+
 #include "base/lazy_instance.h"
-#include "chrome/browser/extensions/global_shortcut_listener.h"
+#include "base/mac/scoped_nsobject.h"
 
 namespace extensions {
 
 // Mac-specific implementation of the GlobalShortcutListener class that
 // listens for global shortcuts. Handles basic keyboard intercepting and
 // forwards its output to the base class for processing.
-// TODO(finnur/smus): Implement this class.
+//
+// This class does two things:
+// 1. Intercepts media keys. Uses an event tap for intercepting media keys
+// (PlayPause, NextTrack, PreviousTrack).
+// 2. Binds keyboard shortcuts (hot keys). Carbon RegisterEventHotKey API for
+// binding to non-media key global hot keys (eg. Command-Shift-1).
 class GlobalShortcutListenerMac : public GlobalShortcutListener {
  public:
   virtual ~GlobalShortcutListenerMac();
 
   virtual void StartListening() OVERRIDE;
   virtual void StopListening() OVERRIDE;
 
+  // Keyboard event callbacks.
+  bool OnKeyEvent(EventHotKeyID hot_key_id);
+  bool OnMediaKeyEvent(int key_code);
+
  private:
   friend struct base::DefaultLazyInstanceTraits<GlobalShortcutListenerMac>;
 
   GlobalShortcutListenerMac();
 
   // Register an |accelerator| with the particular |observer|.
   virtual void RegisterAccelerator(
       const ui::Accelerator& accelerator,
       GlobalShortcutListener::Observer* observer) OVERRIDE;
   // Unregister an |accelerator| with the particular |observer|.
   virtual void UnregisterAccelerator(
       const ui::Accelerator& accelerator,
       GlobalShortcutListener::Observer* observer) OVERRIDE;
 
+  // Mac-specific functions for registering hot keys with modifiers.
+  void RegisterHotKey(const ui::Accelerator& accelerator, int hot_key_id);
+  void UnregisterHotKey(const ui::Accelerator& accelerator);
+
+  // Enable and disable the media key event tap.
+  void StartWatchingMediaKeys();
+  void StopWatchingMediaKeys();
+
+  // Whether or not any media keys are currently registered.
+  bool IsAnyMediaKeyRegistered();
+
+  // The callback for when an event tap happens.
+  static CGEventRef EventTapCallback(
+      CGEventTapProxy proxy, CGEventType type, CGEventRef event, void* refcon);
+
   // Whether this object is listening for global shortcuts.
   bool is_listening_;
 
+  // The hotkey identifier for the next global shortcut that is added.
+  int hot_key_id_;

[Mark Mentovai, 2013/12/09 19:31:54]

There are a bunch of different things in here that use int, and it’s not
straightforward to tell if they’re all the same, or which ones are the same. Use
typedefs to make the code more meaningful. Maybe there are already typedefs
defined elsewhere that you can use. If not, introduce some.

[smus, 2013/12/09 23:37:06]

Done.

+
+  // A map of all hotkeys (media keys and shortcuts) mapping to their
+  // corresponding hotkey IDs. For quickly finding if an accelerator is
+  // registered.
+  typedef std::map<ui::Accelerator, int> HotKeyIdMap;
+  HotKeyIdMap hot_key_ids_;
+
+  // The inverse map for quickly looking up accelerators by hotkey id.
+  typedef std::map<int, ui::Accelerator> IdHotKeyMap;
+  IdHotKeyMap id_hot_keys_;
+
+  // Keyboard shortcut IDs to hotkeys map for unregistration.
+  typedef std::map<int, EventHotKeyRef> IdHotKeyRefMap;
+  IdHotKeyRefMap id_hot_key_refs_;
+
+  // Event tap for intercepting mac media keys.
+  CFMachPortRef event_tap_;
+  CFRunLoopSourceRef event_tap_source_;
+
   DISALLOW_COPY_AND_ASSIGN(GlobalShortcutListenerMac);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_GLOBAL_SHORTCUT_LISTENER_MAC_H_