Function2.html
19.7 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>The source code</title>
<link href="../resources/prettify/prettify.css" type="text/css" rel="stylesheet" />
<script type="text/javascript" src="../resources/prettify/prettify.js"></script>
<style type="text/css">
.highlight { display: block; background-color: #ddd; }
</style>
<script type="text/javascript">
function highlight() {
document.getElementById(location.hash.replace(/#/, "")).className = "highlight";
}
</script>
</head>
<body onload="prettyPrint(); highlight();">
<pre class="prettyprint lang-js"><span id='Ext-Function'>/**
</span> * @class Ext.Function
*
* A collection of useful static methods to deal with function callbacks
* @singleton
* @alternateClassName Ext.util.Functions
*/
Ext.Function = {
<span id='Ext-Function-method-flexSetter'> /**
</span> * A very commonly used method throughout the framework. It acts as a wrapper around another method
* which originally accepts 2 arguments for `name` and `value`.
* The wrapped function then allows "flexible" value setting of either:
*
* - `name` and `value` as 2 arguments
* - one single object argument with multiple key - value pairs
*
* For example:
*
* var setValue = Ext.Function.flexSetter(function(name, value) {
* this[name] = value;
* });
*
* // Afterwards
* // Setting a single name - value
* setValue('name1', 'value1');
*
* // Settings multiple name - value pairs
* setValue({
* name1: 'value1',
* name2: 'value2',
* name3: 'value3'
* });
*
* @param {Function} setter
* @returns {Function} flexSetter
*/
flexSetter: function(fn) {
return function(a, b) {
var k, i;
if (a === null) {
return this;
}
if (typeof a !== 'string') {
for (k in a) {
if (a.hasOwnProperty(k)) {
fn.call(this, k, a[k]);
}
}
if (Ext.enumerables) {
for (i = Ext.enumerables.length; i--;) {
k = Ext.enumerables[i];
if (a.hasOwnProperty(k)) {
fn.call(this, k, a[k]);
}
}
}
} else {
fn.call(this, a, b);
}
return this;
};
},
<span id='Ext-Function-method-bind'> /**
</span> * Create a new function from the provided `fn`, change `this` to the provided scope, optionally
* overrides arguments for the call. (Defaults to the arguments passed by the caller)
*
* {@link Ext#bind Ext.bind} is alias for {@link Ext.Function#bind Ext.Function.bind}
*
* @param {Function} fn The function to delegate.
* @param {Object} scope (optional) The scope (`this` reference) in which the function is executed.
* **If omitted, defaults to the default global environment object (usually the browser window).**
* @param {Array} args (optional) Overrides arguments for the call. (Defaults to the arguments passed by the caller)
* @param {Boolean/Number} appendArgs (optional) if True args are appended to call args instead of overriding,
* if a number the args are inserted at the specified position
* @return {Function} The new function
*/
bind: function(fn, scope, args, appendArgs) {
if (arguments.length === 2) {
return function() {
return fn.apply(scope, arguments);
};
}
var method = fn,
slice = Array.prototype.slice;
return function() {
var callArgs = args || arguments;
if (appendArgs === true) {
callArgs = slice.call(arguments, 0);
callArgs = callArgs.concat(args);
}
else if (typeof appendArgs == 'number') {
callArgs = slice.call(arguments, 0); // copy arguments first
Ext.Array.insert(callArgs, appendArgs, args);
}
return method.apply(scope || Ext.global, callArgs);
};
},
<span id='Ext-Function-method-pass'> /**
</span> * Create a new function from the provided `fn`, the arguments of which are pre-set to `args`.
* New arguments passed to the newly created callback when it's invoked are appended after the pre-set ones.
* This is especially useful when creating callbacks.
*
* For example:
*
* var originalFunction = function(){
* alert(Ext.Array.from(arguments).join(' '));
* };
*
* var callback = Ext.Function.pass(originalFunction, ['Hello', 'World']);
*
* callback(); // alerts 'Hello World'
* callback('by Me'); // alerts 'Hello World by Me'
*
* {@link Ext#pass Ext.pass} is alias for {@link Ext.Function#pass Ext.Function.pass}
*
* @param {Function} fn The original function
* @param {Array} args The arguments to pass to new callback
* @param {Object} scope (optional) The scope (`this` reference) in which the function is executed.
* @return {Function} The new callback function
*/
pass: function(fn, args, scope) {
if (!Ext.isArray(args)) {
if (Ext.isIterable(args)) {
args = Ext.Array.clone(args);
} else {
args = args !== undefined ? [args] : [];
}
}
return function() {
var fnArgs = [].concat(args);
fnArgs.push.apply(fnArgs, arguments);
return fn.apply(scope || this, fnArgs);
};
},
<span id='Ext-Function-method-alias'> /**
</span> * Create an alias to the provided method property with name `methodName` of `object`.
* Note that the execution scope will still be bound to the provided `object` itself.
*
* @param {Object/Function} object
* @param {String} methodName
* @return {Function} aliasFn
*/
alias: function(object, methodName) {
return function() {
return object[methodName].apply(object, arguments);
};
},
<span id='Ext-Function-method-clone'> /**
</span> * Create a "clone" of the provided method. The returned method will call the given
* method passing along all arguments and the "this" pointer and return its result.
*
* @param {Function} method
* @return {Function} cloneFn
*/
clone: function(method) {
return function() {
return method.apply(this, arguments);
};
},
<span id='Ext-Function-method-createInterceptor'> /**
</span> * Creates an interceptor function. The passed function is called before the original one. If it returns false,
* the original one is not called. The resulting function returns the results of the original function.
* The passed function is called with the parameters of the original function. Example usage:
*
* var sayHi = function(name){
* alert('Hi, ' + name);
* }
*
* sayHi('Fred'); // alerts "Hi, Fred"
*
* // create a new function that validates input without
* // directly modifying the original function:
* var sayHiToFriend = Ext.Function.createInterceptor(sayHi, function(name){
* return name == 'Brian';
* });
*
* sayHiToFriend('Fred'); // no alert
* sayHiToFriend('Brian'); // alerts "Hi, Brian"
*
* @param {Function} origFn The original function.
* @param {Function} newFn The function to call before the original
* @param {Object} scope (optional) The scope (`this` reference) in which the passed function is executed.
* **If omitted, defaults to the scope in which the original function is called or the browser window.**
* @param {Object} returnValue (optional) The value to return if the passed function return false (defaults to null).
* @return {Function} The new function
*/
createInterceptor: function(origFn, newFn, scope, returnValue) {
var method = origFn;
if (!Ext.isFunction(newFn)) {
return origFn;
}
else {
return function() {
var me = this,
args = arguments;
newFn.target = me;
newFn.method = origFn;
return (newFn.apply(scope || me || Ext.global, args) !== false) ? origFn.apply(me || Ext.global, args) : returnValue || null;
};
}
},
<span id='Ext-Function-method-createDelayed'> /**
</span> * Creates a delegate (callback) which, when called, executes after a specific delay.
*
* @param {Function} fn The function which will be called on a delay when the returned function is called.
* Optionally, a replacement (or additional) argument list may be specified.
* @param {Number} delay The number of milliseconds to defer execution by whenever called.
* @param {Object} scope (optional) The scope (`this` reference) used by the function at execution time.
* @param {Array} args (optional) Override arguments for the call. (Defaults to the arguments passed by the caller)
* @param {Boolean/Number} appendArgs (optional) if True args are appended to call args instead of overriding,
* if a number the args are inserted at the specified position.
* @return {Function} A function which, when called, executes the original function after the specified delay.
*/
createDelayed: function(fn, delay, scope, args, appendArgs) {
if (scope || args) {
fn = Ext.Function.bind(fn, scope, args, appendArgs);
}
return function() {
var me = this,
args = Array.prototype.slice.call(arguments);
setTimeout(function() {
fn.apply(me, args);
}, delay);
};
},
<span id='Ext-Function-method-defer'> /**
</span> * Calls this function after the number of millseconds specified, optionally in a specific scope. Example usage:
*
* var sayHi = function(name){
* alert('Hi, ' + name);
* }
*
* // executes immediately:
* sayHi('Fred');
*
* // executes after 2 seconds:
* Ext.Function.defer(sayHi, 2000, this, ['Fred']);
*
* // this syntax is sometimes useful for deferring
* // execution of an anonymous function:
* Ext.Function.defer(function(){
* alert('Anonymous');
* }, 100);
*
* {@link Ext#defer Ext.defer} is alias for {@link Ext.Function#defer Ext.Function.defer}
*
* @param {Function} fn The function to defer.
* @param {Number} millis The number of milliseconds for the setTimeout call
* (if less than or equal to 0 the function is executed immediately)
* @param {Object} scope (optional) The scope (`this` reference) in which the function is executed.
* **If omitted, defaults to the browser window.**
* @param {Array} args (optional) Overrides arguments for the call. (Defaults to the arguments passed by the caller)
* @param {Boolean/Number} appendArgs (optional) if True args are appended to call args instead of overriding,
* if a number the args are inserted at the specified position
* @return {Number} The timeout id that can be used with clearTimeout
*/
defer: function(fn, millis, scope, args, appendArgs) {
fn = Ext.Function.bind(fn, scope, args, appendArgs);
if (millis > 0) {
return setTimeout(Ext.supports.TimeoutActualLateness ? function () {
fn();
} : fn, millis);
}
fn();
return 0;
},
<span id='Ext-Function-method-createSequence'> /**
</span> * Create a combined function call sequence of the original function + the passed function.
* The resulting function returns the results of the original function.
* The passed function is called with the parameters of the original function. Example usage:
*
* var sayHi = function(name){
* alert('Hi, ' + name);
* }
*
* sayHi('Fred'); // alerts "Hi, Fred"
*
* var sayGoodbye = Ext.Function.createSequence(sayHi, function(name){
* alert('Bye, ' + name);
* });
*
* sayGoodbye('Fred'); // both alerts show
*
* @param {Function} originalFn The original function.
* @param {Function} newFn The function to sequence
* @param {Object} scope (optional) The scope (`this` reference) in which the passed function is executed.
* If omitted, defaults to the scope in which the original function is called or the default global environment object (usually the browser window).
* @return {Function} The new function
*/
createSequence: function(originalFn, newFn, scope) {
if (!newFn) {
return originalFn;
}
else {
return function() {
var result = originalFn.apply(this, arguments);
newFn.apply(scope || this, arguments);
return result;
};
}
},
<span id='Ext-Function-method-createBuffered'> /**
</span> * Creates a delegate function, optionally with a bound scope which, when called, buffers
* the execution of the passed function for the configured number of milliseconds.
* If called again within that period, the impending invocation will be canceled, and the
* timeout period will begin again.
*
* @param {Function} fn The function to invoke on a buffered timer.
* @param {Number} buffer The number of milliseconds by which to buffer the invocation of the
* function.
* @param {Object} scope (optional) The scope (`this` reference) in which
* the passed function is executed. If omitted, defaults to the scope specified by the caller.
* @param {Array} args (optional) Override arguments for the call. Defaults to the arguments
* passed by the caller.
* @return {Function} A function which invokes the passed function after buffering for the specified time.
*/
createBuffered: function(fn, buffer, scope, args) {
var timerId;
return function() {
var callArgs = args || Array.prototype.slice.call(arguments, 0),
me = scope || this;
if (timerId) {
clearTimeout(timerId);
}
timerId = setTimeout(function(){
fn.apply(me, callArgs);
}, buffer);
};
},
<span id='Ext-Function-method-createThrottled'> /**
</span> * Creates a throttled version of the passed function which, when called repeatedly and
* rapidly, invokes the passed function only after a certain interval has elapsed since the
* previous invocation.
*
* This is useful for wrapping functions which may be called repeatedly, such as
* a handler of a mouse move event when the processing is expensive.
*
* @param {Function} fn The function to execute at a regular time interval.
* @param {Number} interval The interval **in milliseconds** on which the passed function is executed.
* @param {Object} scope (optional) The scope (`this` reference) in which
* the passed function is executed. If omitted, defaults to the scope specified by the caller.
* @returns {Function} A function which invokes the passed function at the specified interval.
*/
createThrottled: function(fn, interval, scope) {
var lastCallTime, elapsed, lastArgs, timer, execute = function() {
fn.apply(scope || this, lastArgs);
lastCallTime = new Date().getTime();
};
return function() {
elapsed = new Date().getTime() - lastCallTime;
lastArgs = arguments;
clearTimeout(timer);
if (!lastCallTime || (elapsed >= interval)) {
execute();
} else {
timer = setTimeout(execute, interval - elapsed);
}
};
},
<span id='Ext-Function-method-interceptBefore'> /**
</span> * Adds behavior to an existing method that is executed before the
* original behavior of the function. For example:
*
* var soup = {
* contents: [],
* add: function(ingredient) {
* this.contents.push(ingredient);
* }
* };
* Ext.Function.interceptBefore(soup, "add", function(ingredient){
* if (!this.contents.length && ingredient !== "water") {
* // Always add water to start with
* this.contents.push("water");
* }
* });
* soup.add("onions");
* soup.add("salt");
* soup.contents; // will contain: water, onions, salt
*
* @param {Object} object The target object
* @param {String} methodName Name of the method to override
* @param {Function} fn Function with the new behavior. It will
* be called with the same arguments as the original method. The
* return value of this function will be the return value of the
* new method.
* @param {Object} [scope] The scope to execute the interceptor function. Defaults to the object.
* @return {Function} The new function just created.
*/
interceptBefore: function(object, methodName, fn, scope) {
var method = object[methodName] || Ext.emptyFn;
return (object[methodName] = function() {
var ret = fn.apply(scope || this, arguments);
method.apply(this, arguments);
return ret;
});
},
<span id='Ext-Function-method-interceptAfter'> /**
</span> * Adds behavior to an existing method that is executed after the
* original behavior of the function. For example:
*
* var soup = {
* contents: [],
* add: function(ingredient) {
* this.contents.push(ingredient);
* }
* };
* Ext.Function.interceptAfter(soup, "add", function(ingredient){
* // Always add a bit of extra salt
* this.contents.push("salt");
* });
* soup.add("water");
* soup.add("onions");
* soup.contents; // will contain: water, salt, onions, salt
*
* @param {Object} object The target object
* @param {String} methodName Name of the method to override
* @param {Function} fn Function with the new behavior. It will
* be called with the same arguments as the original method. The
* return value of this function will be the return value of the
* new method.
* @param {Object} [scope] The scope to execute the interceptor function. Defaults to the object.
* @return {Function} The new function just created.
*/
interceptAfter: function(object, methodName, fn, scope) {
var method = object[methodName] || Ext.emptyFn;
return (object[methodName] = function() {
method.apply(this, arguments);
return fn.apply(scope || this, arguments);
});
}
};
<span id='Ext-method-defer'>/**
</span> * @method
* @member Ext
* @inheritdoc Ext.Function#defer
*/
Ext.defer = Ext.Function.alias(Ext.Function, 'defer');
<span id='Ext-method-pass'>/**
</span> * @method
* @member Ext
* @inheritdoc Ext.Function#pass
*/
Ext.pass = Ext.Function.alias(Ext.Function, 'pass');
<span id='Ext-method-bind'>/**
</span> * @method
* @member Ext
* @inheritdoc Ext.Function#bind
*/
Ext.bind = Ext.Function.alias(Ext.Function, 'bind');
</pre>
</body>
</html>