📝 Shortcut API document.

docs/README.md

@@ -21,6 +21,7 @@ Modules for browser side:
 * [power-monitor](api/power-monitor.md)
 * [protocol](api/protocol.md)
 * [tray](api/tray.md)
+* [shortcut](api/shortcut.md)
 
 Modules for web page:
 

docs/api/shortcut.md

@@ -0,0 +1,67 @@
+# shortcut
+
+A `Shortcut` presents a global keyboard shortcut in operating system. If a 
+`Shortcut` is registered in app, the app will receive an `active` event when
+user presses the shortcut. Note that it is global, even your app does not get 
+focused, it still works.
+
+
+```javascript
+var Shortcut = require('shortcut');
+
+shortcut = new Shortcut('ctrl+a');
+shortcut.setKey('ctrl+s');
+shortcut.on('active', function() { console.log('ctrl+s pressed'); });
+shortcut.on('failed', function() { console.log("failed"); });
+shortcut.register();
+```
+
+## Class: Shortcut 
+
+`Shortcut` is an [EventEmitter](event-emitter).
+
+### new Shortcut(keycode)
+
+* `keycode` String
+
+Creates a new `Shortcut` associated with the `keycode`.
+
+`keycode` is a string to specify shortcut key, such as "ctrl+shift+a".
+
+A `keycode` consists of modifier and key two parts:
+
+__Modifiers__: control(ctrl), command(cmd), alt, shift, commandorcontrol(cmdorctrl).
+
+__Supported keys__: 0-9, a-z, up, down, left, right, home, end, pagedown, pageup,
+insert, delete, esc, space, backspace, tab, f1-f12, volumeup, volumedown, media 
+keys(medianextrack, mediaprevioustrack, mediastop, mediaplaypause).
+
+### Event: active
+
+Emitted when a registered `shortcut` is pressed by user.
+
+### Event: failed
+
+Emitted when the keycode of `shortcut` is invalid.
+
+### Shortcut.setKey(keycode)
+
+* `keycode` String 
+
+Set new `keycode` to a `Shortcut`. Note that this operation will override previous
+keycode and will unregister the `Shortcut`, developer should register the
+`Shortcut` again after `setKey`.
+
+### Shortcut.register
+
+Register a `Shortcut` to operating system.
+
+### Shortcut.unregister
+
+Unregister a `Shortcut` to operating system.
+
+### Shortcut.isRegistered
+
+Return whether the shortcut is registered.
+
+[event-emitter]: http://nodejs.org/api/events.html#events_class_events_eventemitter