jennschiffer.com
make8bitart.com
1// keymaster.js
2// (c) 2011-2013 Thomas Fuchs
3// keymaster.js may be freely distributed under the MIT license.
4
5;(function(global){
6 var k,
7 _handlers = {},
8 _mods = { 16: false, 18: false, 17: false, 91: false },
9 _scope = 'all',
10 // modifier keys
11 _MODIFIERS = {
12 '⇧': 16, shift: 16,
13 '⌥': 18, alt: 18, option: 18,
14 '⌃': 17, ctrl: 17, control: 17,
15 '⌘': 91, command: 91
16 },
17 // special keys
18 _MAP = {
19 backspace: 8, tab: 9, clear: 12,
20 enter: 13, 'return': 13,
21 esc: 27, escape: 27, space: 32,
22 left: 37, up: 38,
23 right: 39, down: 40,
24 del: 46, 'delete': 46,
25 home: 36, end: 35,
26 pageup: 33, pagedown: 34,
27 ',': 188, '.': 190, '/': 191,
28 '`': 192, '-': 189, '=': 187,
29 ';': 186, '\'': 222,
30 '[': 219, ']': 221, '\\': 220
31 },
32 code = function(x){
33 return _MAP[x] || x.toUpperCase().charCodeAt(0);
34 },
35 _downKeys = [];
36
37 for(k=1;k<20;k++) _MAP['f'+k] = 111+k;
38
39 // IE doesn't support Array#indexOf, so have a simple replacement
40 function index(array, item){
41 var i = array.length;
42 while(i--) if(array[i]===item) return i;
43 return -1;
44 }
45
46 // for comparing mods before unassignment
47 function compareArray(a1, a2) {
48 if (a1.length != a2.length) return false;
49 for (var i = 0; i < a1.length; i++) {
50 if (a1[i] !== a2[i]) return false;
51 }
52 return true;
53 }
54
55 var modifierMap = {
56 16:'shiftKey',
57 18:'altKey',
58 17:'ctrlKey',
59 91:'metaKey'
60 };
61 function updateModifierKey(event) {
62 for(k in _mods) _mods[k] = event[modifierMap[k]];
63 };
64
65 // handle keydown event
66 function dispatch(event) {
67 var key, handler, k, i, modifiersMatch, scope;
68 key = event.keyCode;
69
70 if (index(_downKeys, key) == -1) {
71 _downKeys.push(key);
72 }
73
74 // if a modifier key, set the key.<modifierkeyname> property to true and return
75 if(key == 93 || key == 224) key = 91; // right command on webkit, command on Gecko
76 if(key in _mods) {
77 _mods[key] = true;
78 // 'assignKey' from inside this closure is exported to window.key
79 for(k in _MODIFIERS) if(_MODIFIERS[k] == key) assignKey[k] = true;
80 return;
81 }
82 updateModifierKey(event);
83
84 // see if we need to ignore the keypress (filter() can can be overridden)
85 // by default ignore key presses if a select, textarea, or input is focused
86 if(!assignKey.filter.call(this, event)) return;
87
88 // abort if no potentially matching shortcuts found
89 if (!(key in _handlers)) return;
90
91 scope = getScope();
92
93 // for each potential shortcut
94 for (i = 0; i < _handlers[key].length; i++) {
95 handler = _handlers[key][i];
96
97 // see if it's in the current scope
98 if(handler.scope == scope || handler.scope == 'all'){
99 // check if modifiers match if any
100 modifiersMatch = handler.mods.length > 0;
101 for(k in _mods)
102 if((!_mods[k] && index(handler.mods, +k) > -1) ||
103 (_mods[k] && index(handler.mods, +k) == -1)) modifiersMatch = false;
104 // call the handler and stop the event if neccessary
105 if((handler.mods.length == 0 && !_mods[16] && !_mods[18] && !_mods[17] && !_mods[91]) || modifiersMatch){
106 if(handler.method(event, handler)===false){
107 if(event.preventDefault) event.preventDefault();
108 else event.returnValue = false;
109 if(event.stopPropagation) event.stopPropagation();
110 if(event.cancelBubble) event.cancelBubble = true;
111 }
112 }
113 }
114 }
115 };
116
117 // unset modifier keys on keyup
118 function clearModifier(event){
119 var key = event.keyCode, k,
120 i = index(_downKeys, key);
121
122 // remove key from _downKeys
123 if (i >= 0) {
124 _downKeys.splice(i, 1);
125 }
126
127 if(key == 93 || key == 224) key = 91;
128 if(key in _mods) {
129 _mods[key] = false;
130 for(k in _MODIFIERS) if(_MODIFIERS[k] == key) assignKey[k] = false;
131 }
132 };
133
134 function resetModifiers() {
135 for(k in _mods) _mods[k] = false;
136 for(k in _MODIFIERS) assignKey[k] = false;
137 };
138
139 // parse and assign shortcut
140 function assignKey(key, scope, method){
141 var keys, mods;
142 keys = getKeys(key);
143 if (method === undefined) {
144 method = scope;
145 scope = 'all';
146 }
147
148 // for each shortcut
149 for (var i = 0; i < keys.length; i++) {
150 // set modifier keys if any
151 mods = [];
152 key = keys[i].split('+');
153 if (key.length > 1){
154 mods = getMods(key);
155 key = [key[key.length-1]];
156 }
157 // convert to keycode and...
158 key = key[0]
159 key = code(key);
160 // ...store handler
161 if (!(key in _handlers)) _handlers[key] = [];
162 _handlers[key].push({ shortcut: keys[i], scope: scope, method: method, key: keys[i], mods: mods });
163 }
164 };
165
166 // unbind all handlers for given key in current scope
167 function unbindKey(key, scope) {
168 var multipleKeys, keys,
169 mods = [],
170 i, j, obj;
171
172 multipleKeys = getKeys(key);
173
174 for (j = 0; j < multipleKeys.length; j++) {
175 keys = multipleKeys[j].split('+');
176
177 if (keys.length > 1) {
178 mods = getMods(keys);
179 key = keys[keys.length - 1];
180 }
181
182 key = code(key);
183
184 if (scope === undefined) {
185 scope = getScope();
186 }
187 if (!_handlers[key]) {
188 return;
189 }
190 for (i in _handlers[key]) {
191 obj = _handlers[key][i];
192 // only clear handlers if correct scope and mods match
193 if (obj.scope === scope && compareArray(obj.mods, mods)) {
194 _handlers[key][i] = {};
195 }
196 }
197 }
198 };
199
200 // Returns true if the key with code 'keyCode' is currently down
201 // Converts strings into key codes.
202 function isPressed(keyCode) {
203 if (typeof(keyCode)=='string') {
204 keyCode = code(keyCode);
205 }
206 return index(_downKeys, keyCode) != -1;
207 }
208
209 function getPressedKeyCodes() {
210 return _downKeys.slice(0);
211 }
212
213 function filter(event){
214 var tagName = (event.target || event.srcElement).tagName;
215 // ignore keypressed in any elements that support keyboard data input
216 return !(tagName == 'INPUT' || tagName == 'SELECT' || tagName == 'TEXTAREA');
217 }
218
219 // initialize key.<modifier> to false
220 for(k in _MODIFIERS) assignKey[k] = false;
221
222 // set current scope (default 'all')
223 function setScope(scope){ _scope = scope || 'all' };
224 function getScope(){ return _scope || 'all' };
225
226 // delete all handlers for a given scope
227 function deleteScope(scope){
228 var key, handlers, i;
229
230 for (key in _handlers) {
231 handlers = _handlers[key];
232 for (i = 0; i < handlers.length; ) {
233 if (handlers[i].scope === scope) handlers.splice(i, 1);
234 else i++;
235 }
236 }
237 };
238
239 // abstract key logic for assign and unassign
240 function getKeys(key) {
241 var keys;
242 key = key.replace(/\s/g, '');
243 keys = key.split(',');
244 if ((keys[keys.length - 1]) == '') {
245 keys[keys.length - 2] += ',';
246 }
247 return keys;
248 }
249
250 // abstract mods logic for assign and unassign
251 function getMods(key) {
252 var mods = key.slice(0, key.length - 1);
253 for (var mi = 0; mi < mods.length; mi++)
254 mods[mi] = _MODIFIERS[mods[mi]];
255 return mods;
256 }
257
258 // cross-browser events
259 function addEvent(object, event, method) {
260 if (object.addEventListener)
261 object.addEventListener(event, method, false);
262 else if(object.attachEvent)
263 object.attachEvent('on'+event, function(){ method(window.event) });
264 };
265
266 // set the handlers globally on document
267 addEvent(document, 'keydown', function(event) { dispatch(event) }); // Passing _scope to a callback to ensure it remains the same by execution. Fixes #48
268 addEvent(document, 'keyup', clearModifier);
269
270 // reset modifiers to false whenever the window is (re)focused.
271 addEvent(window, 'focus', resetModifiers);
272
273 // store previously defined key
274 var previousKey = global.key;
275
276 // restore previously defined key and return reference to our key object
277 function noConflict() {
278 var k = global.key;
279 global.key = previousKey;
280 return k;
281 }
282
283 // set window.key and window.key.set/get/deleteScope, and the default filter
284 global.key = assignKey;
285 global.key.setScope = setScope;
286 global.key.getScope = getScope;
287 global.key.deleteScope = deleteScope;
288 global.key.filter = filter;
289 global.key.isPressed = isPressed;
290 global.key.getPressedKeyCodes = getPressedKeyCodes;
291 global.key.noConflict = noConflict;
292 global.key.unbind = unbindKey;
293
294 if(typeof module !== 'undefined') module.exports = key;
295
296})(this);