comparison src/DML/VendorAssetsBundle/Resources/assets/fastclick/1.0.3/fastclick.js @ 0:493bcb69166c

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author Daniel Wolff
date Tue, 09 Feb 2016 20:54:02 +0100
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1 (function () {
2 'use strict';
3
4 /**
5 * @preserve FastClick: polyfill to remove click delays on browsers with touch UIs.
6 *
7 * @version 1.0.3
8 * @codingstandard ftlabs-jsv2
9 * @copyright The Financial Times Limited [All Rights Reserved]
10 * @license MIT License (see LICENSE.txt)
11 */
12
13 /*jslint browser:true, node:true*/
14 /*global define, Event, Node*/
15
16
17 /**
18 * Instantiate fast-clicking listeners on the specified layer.
19 *
20 * @constructor
21 * @param {Element} layer The layer to listen on
22 * @param {Object} options The options to override the defaults
23 */
24 function FastClick(layer, options) {
25 var oldOnClick;
26
27 options = options || {};
28
29 /**
30 * Whether a click is currently being tracked.
31 *
32 * @type boolean
33 */
34 this.trackingClick = false;
35
36
37 /**
38 * Timestamp for when click tracking started.
39 *
40 * @type number
41 */
42 this.trackingClickStart = 0;
43
44
45 /**
46 * The element being tracked for a click.
47 *
48 * @type EventTarget
49 */
50 this.targetElement = null;
51
52
53 /**
54 * X-coordinate of touch start event.
55 *
56 * @type number
57 */
58 this.touchStartX = 0;
59
60
61 /**
62 * Y-coordinate of touch start event.
63 *
64 * @type number
65 */
66 this.touchStartY = 0;
67
68
69 /**
70 * ID of the last touch, retrieved from Touch.identifier.
71 *
72 * @type number
73 */
74 this.lastTouchIdentifier = 0;
75
76
77 /**
78 * Touchmove boundary, beyond which a click will be cancelled.
79 *
80 * @type number
81 */
82 this.touchBoundary = options.touchBoundary || 10;
83
84
85 /**
86 * The FastClick layer.
87 *
88 * @type Element
89 */
90 this.layer = layer;
91
92 /**
93 * The minimum time between tap(touchstart and touchend) events
94 *
95 * @type number
96 */
97 this.tapDelay = options.tapDelay || 200;
98
99 if (FastClick.notNeeded(layer)) {
100 return;
101 }
102
103 // Some old versions of Android don't have Function.prototype.bind
104 function bind(method, context) {
105 return function() { return method.apply(context, arguments); };
106 }
107
108
109 var methods = ['onMouse', 'onClick', 'onTouchStart', 'onTouchMove', 'onTouchEnd', 'onTouchCancel'];
110 var context = this;
111 for (var i = 0, l = methods.length; i < l; i++) {
112 context[methods[i]] = bind(context[methods[i]], context);
113 }
114
115 // Set up event handlers as required
116 if (deviceIsAndroid) {
117 layer.addEventListener('mouseover', this.onMouse, true);
118 layer.addEventListener('mousedown', this.onMouse, true);
119 layer.addEventListener('mouseup', this.onMouse, true);
120 }
121
122 layer.addEventListener('click', this.onClick, true);
123 layer.addEventListener('touchstart', this.onTouchStart, false);
124 layer.addEventListener('touchmove', this.onTouchMove, false);
125 layer.addEventListener('touchend', this.onTouchEnd, false);
126 layer.addEventListener('touchcancel', this.onTouchCancel, false);
127
128 // Hack is required for browsers that don't support Event#stopImmediatePropagation (e.g. Android 2)
129 // which is how FastClick normally stops click events bubbling to callbacks registered on the FastClick
130 // layer when they are cancelled.
131 if (!Event.prototype.stopImmediatePropagation) {
132 layer.removeEventListener = function(type, callback, capture) {
133 var rmv = Node.prototype.removeEventListener;
134 if (type === 'click') {
135 rmv.call(layer, type, callback.hijacked || callback, capture);
136 } else {
137 rmv.call(layer, type, callback, capture);
138 }
139 };
140
141 layer.addEventListener = function(type, callback, capture) {
142 var adv = Node.prototype.addEventListener;
143 if (type === 'click') {
144 adv.call(layer, type, callback.hijacked || (callback.hijacked = function(event) {
145 if (!event.propagationStopped) {
146 callback(event);
147 }
148 }), capture);
149 } else {
150 adv.call(layer, type, callback, capture);
151 }
152 };
153 }
154
155 // If a handler is already declared in the element's onclick attribute, it will be fired before
156 // FastClick's onClick handler. Fix this by pulling out the user-defined handler function and
157 // adding it as listener.
158 if (typeof layer.onclick === 'function') {
159
160 // Android browser on at least 3.2 requires a new reference to the function in layer.onclick
161 // - the old one won't work if passed to addEventListener directly.
162 oldOnClick = layer.onclick;
163 layer.addEventListener('click', function(event) {
164 oldOnClick(event);
165 }, false);
166 layer.onclick = null;
167 }
168 }
169
170
171 /**
172 * Android requires exceptions.
173 *
174 * @type boolean
175 */
176 var deviceIsAndroid = navigator.userAgent.indexOf('Android') > 0;
177
178
179 /**
180 * iOS requires exceptions.
181 *
182 * @type boolean
183 */
184 var deviceIsIOS = /iP(ad|hone|od)/.test(navigator.userAgent);
185
186
187 /**
188 * iOS 4 requires an exception for select elements.
189 *
190 * @type boolean
191 */
192 var deviceIsIOS4 = deviceIsIOS && (/OS 4_\d(_\d)?/).test(navigator.userAgent);
193
194
195 /**
196 * iOS 6.0(+?) requires the target element to be manually derived
197 *
198 * @type boolean
199 */
200 var deviceIsIOSWithBadTarget = deviceIsIOS && (/OS ([6-9]|\d{2})_\d/).test(navigator.userAgent);
201
202 /**
203 * BlackBerry requires exceptions.
204 *
205 * @type boolean
206 */
207 var deviceIsBlackBerry10 = navigator.userAgent.indexOf('BB10') > 0;
208
209 /**
210 * Determine whether a given element requires a native click.
211 *
212 * @param {EventTarget|Element} target Target DOM element
213 * @returns {boolean} Returns true if the element needs a native click
214 */
215 FastClick.prototype.needsClick = function(target) {
216 switch (target.nodeName.toLowerCase()) {
217
218 // Don't send a synthetic click to disabled inputs (issue #62)
219 case 'button':
220 case 'select':
221 case 'textarea':
222 if (target.disabled) {
223 return true;
224 }
225
226 break;
227 case 'input':
228
229 // File inputs need real clicks on iOS 6 due to a browser bug (issue #68)
230 if ((deviceIsIOS && target.type === 'file') || target.disabled) {
231 return true;
232 }
233
234 break;
235 case 'label':
236 case 'video':
237 return true;
238 }
239
240 return (/\bneedsclick\b/).test(target.className);
241 };
242
243
244 /**
245 * Determine whether a given element requires a call to focus to simulate click into element.
246 *
247 * @param {EventTarget|Element} target Target DOM element
248 * @returns {boolean} Returns true if the element requires a call to focus to simulate native click.
249 */
250 FastClick.prototype.needsFocus = function(target) {
251 switch (target.nodeName.toLowerCase()) {
252 case 'textarea':
253 return true;
254 case 'select':
255 return !deviceIsAndroid;
256 case 'input':
257 switch (target.type) {
258 case 'button':
259 case 'checkbox':
260 case 'file':
261 case 'image':
262 case 'radio':
263 case 'submit':
264 return false;
265 }
266
267 // No point in attempting to focus disabled inputs
268 return !target.disabled && !target.readOnly;
269 default:
270 return (/\bneedsfocus\b/).test(target.className);
271 }
272 };
273
274
275 /**
276 * Send a click event to the specified element.
277 *
278 * @param {EventTarget|Element} targetElement
279 * @param {Event} event
280 */
281 FastClick.prototype.sendClick = function(targetElement, event) {
282 var clickEvent, touch;
283
284 // On some Android devices activeElement needs to be blurred otherwise the synthetic click will have no effect (#24)
285 if (document.activeElement && document.activeElement !== targetElement) {
286 document.activeElement.blur();
287 }
288
289 touch = event.changedTouches[0];
290
291 // Synthesise a click event, with an extra attribute so it can be tracked
292 clickEvent = document.createEvent('MouseEvents');
293 clickEvent.initMouseEvent(this.determineEventType(targetElement), true, true, window, 1, touch.screenX, touch.screenY, touch.clientX, touch.clientY, false, false, false, false, 0, null);
294 clickEvent.forwardedTouchEvent = true;
295 targetElement.dispatchEvent(clickEvent);
296 };
297
298 FastClick.prototype.determineEventType = function(targetElement) {
299
300 //Issue #159: Android Chrome Select Box does not open with a synthetic click event
301 if (deviceIsAndroid && targetElement.tagName.toLowerCase() === 'select') {
302 return 'mousedown';
303 }
304
305 return 'click';
306 };
307
308
309 /**
310 * @param {EventTarget|Element} targetElement
311 */
312 FastClick.prototype.focus = function(targetElement) {
313 var length;
314
315 // Issue #160: on iOS 7, some input elements (e.g. date datetime) throw a vague TypeError on setSelectionRange. These elements don't have an integer value for the selectionStart and selectionEnd properties, but unfortunately that can't be used for detection because accessing the properties also throws a TypeError. Just check the type instead. Filed as Apple bug #15122724.
316 if (deviceIsIOS && targetElement.setSelectionRange && targetElement.type.indexOf('date') !== 0 && targetElement.type !== 'time') {
317 length = targetElement.value.length;
318 targetElement.setSelectionRange(length, length);
319 } else {
320 targetElement.focus();
321 }
322 };
323
324
325 /**
326 * Check whether the given target element is a child of a scrollable layer and if so, set a flag on it.
327 *
328 * @param {EventTarget|Element} targetElement
329 */
330 FastClick.prototype.updateScrollParent = function(targetElement) {
331 var scrollParent, parentElement;
332
333 scrollParent = targetElement.fastClickScrollParent;
334
335 // Attempt to discover whether the target element is contained within a scrollable layer. Re-check if the
336 // target element was moved to another parent.
337 if (!scrollParent || !scrollParent.contains(targetElement)) {
338 parentElement = targetElement;
339 do {
340 if (parentElement.scrollHeight > parentElement.offsetHeight) {
341 scrollParent = parentElement;
342 targetElement.fastClickScrollParent = parentElement;
343 break;
344 }
345
346 parentElement = parentElement.parentElement;
347 } while (parentElement);
348 }
349
350 // Always update the scroll top tracker if possible.
351 if (scrollParent) {
352 scrollParent.fastClickLastScrollTop = scrollParent.scrollTop;
353 }
354 };
355
356
357 /**
358 * @param {EventTarget} targetElement
359 * @returns {Element|EventTarget}
360 */
361 FastClick.prototype.getTargetElementFromEventTarget = function(eventTarget) {
362
363 // On some older browsers (notably Safari on iOS 4.1 - see issue #56) the event target may be a text node.
364 if (eventTarget.nodeType === Node.TEXT_NODE) {
365 return eventTarget.parentNode;
366 }
367
368 return eventTarget;
369 };
370
371
372 /**
373 * On touch start, record the position and scroll offset.
374 *
375 * @param {Event} event
376 * @returns {boolean}
377 */
378 FastClick.prototype.onTouchStart = function(event) {
379 var targetElement, touch, selection;
380
381 // Ignore multiple touches, otherwise pinch-to-zoom is prevented if both fingers are on the FastClick element (issue #111).
382 if (event.targetTouches.length > 1) {
383 return true;
384 }
385
386 targetElement = this.getTargetElementFromEventTarget(event.target);
387 touch = event.targetTouches[0];
388
389 if (deviceIsIOS) {
390
391 // Only trusted events will deselect text on iOS (issue #49)
392 selection = window.getSelection();
393 if (selection.rangeCount && !selection.isCollapsed) {
394 return true;
395 }
396
397 if (!deviceIsIOS4) {
398
399 // Weird things happen on iOS when an alert or confirm dialog is opened from a click event callback (issue #23):
400 // when the user next taps anywhere else on the page, new touchstart and touchend events are dispatched
401 // with the same identifier as the touch event that previously triggered the click that triggered the alert.
402 // Sadly, there is an issue on iOS 4 that causes some normal touch events to have the same identifier as an
403 // immediately preceeding touch event (issue #52), so this fix is unavailable on that platform.
404 // Issue 120: touch.identifier is 0 when Chrome dev tools 'Emulate touch events' is set with an iOS device UA string,
405 // which causes all touch events to be ignored. As this block only applies to iOS, and iOS identifiers are always long,
406 // random integers, it's safe to to continue if the identifier is 0 here.
407 if (touch.identifier && touch.identifier === this.lastTouchIdentifier) {
408 event.preventDefault();
409 return false;
410 }
411
412 this.lastTouchIdentifier = touch.identifier;
413
414 // If the target element is a child of a scrollable layer (using -webkit-overflow-scrolling: touch) and:
415 // 1) the user does a fling scroll on the scrollable layer
416 // 2) the user stops the fling scroll with another tap
417 // then the event.target of the last 'touchend' event will be the element that was under the user's finger
418 // when the fling scroll was started, causing FastClick to send a click event to that layer - unless a check
419 // is made to ensure that a parent layer was not scrolled before sending a synthetic click (issue #42).
420 this.updateScrollParent(targetElement);
421 }
422 }
423
424 this.trackingClick = true;
425 this.trackingClickStart = event.timeStamp;
426 this.targetElement = targetElement;
427
428 this.touchStartX = touch.pageX;
429 this.touchStartY = touch.pageY;
430
431 // Prevent phantom clicks on fast double-tap (issue #36)
432 if ((event.timeStamp - this.lastClickTime) < this.tapDelay) {
433 event.preventDefault();
434 }
435
436 return true;
437 };
438
439
440 /**
441 * Based on a touchmove event object, check whether the touch has moved past a boundary since it started.
442 *
443 * @param {Event} event
444 * @returns {boolean}
445 */
446 FastClick.prototype.touchHasMoved = function(event) {
447 var touch = event.changedTouches[0], boundary = this.touchBoundary;
448
449 if (Math.abs(touch.pageX - this.touchStartX) > boundary || Math.abs(touch.pageY - this.touchStartY) > boundary) {
450 return true;
451 }
452
453 return false;
454 };
455
456
457 /**
458 * Update the last position.
459 *
460 * @param {Event} event
461 * @returns {boolean}
462 */
463 FastClick.prototype.onTouchMove = function(event) {
464 if (!this.trackingClick) {
465 return true;
466 }
467
468 // If the touch has moved, cancel the click tracking
469 if (this.targetElement !== this.getTargetElementFromEventTarget(event.target) || this.touchHasMoved(event)) {
470 this.trackingClick = false;
471 this.targetElement = null;
472 }
473
474 return true;
475 };
476
477
478 /**
479 * Attempt to find the labelled control for the given label element.
480 *
481 * @param {EventTarget|HTMLLabelElement} labelElement
482 * @returns {Element|null}
483 */
484 FastClick.prototype.findControl = function(labelElement) {
485
486 // Fast path for newer browsers supporting the HTML5 control attribute
487 if (labelElement.control !== undefined) {
488 return labelElement.control;
489 }
490
491 // All browsers under test that support touch events also support the HTML5 htmlFor attribute
492 if (labelElement.htmlFor) {
493 return document.getElementById(labelElement.htmlFor);
494 }
495
496 // If no for attribute exists, attempt to retrieve the first labellable descendant element
497 // the list of which is defined here: http://www.w3.org/TR/html5/forms.html#category-label
498 return labelElement.querySelector('button, input:not([type=hidden]), keygen, meter, output, progress, select, textarea');
499 };
500
501
502 /**
503 * On touch end, determine whether to send a click event at once.
504 *
505 * @param {Event} event
506 * @returns {boolean}
507 */
508 FastClick.prototype.onTouchEnd = function(event) {
509 var forElement, trackingClickStart, targetTagName, scrollParent, touch, targetElement = this.targetElement;
510
511 if (!this.trackingClick) {
512 return true;
513 }
514
515 // Prevent phantom clicks on fast double-tap (issue #36)
516 if ((event.timeStamp - this.lastClickTime) < this.tapDelay) {
517 this.cancelNextClick = true;
518 return true;
519 }
520
521 // Reset to prevent wrong click cancel on input (issue #156).
522 this.cancelNextClick = false;
523
524 this.lastClickTime = event.timeStamp;
525
526 trackingClickStart = this.trackingClickStart;
527 this.trackingClick = false;
528 this.trackingClickStart = 0;
529
530 // On some iOS devices, the targetElement supplied with the event is invalid if the layer
531 // is performing a transition or scroll, and has to be re-detected manually. Note that
532 // for this to function correctly, it must be called *after* the event target is checked!
533 // See issue #57; also filed as rdar://13048589 .
534 if (deviceIsIOSWithBadTarget) {
535 touch = event.changedTouches[0];
536
537 // In certain cases arguments of elementFromPoint can be negative, so prevent setting targetElement to null
538 targetElement = document.elementFromPoint(touch.pageX - window.pageXOffset, touch.pageY - window.pageYOffset) || targetElement;
539 targetElement.fastClickScrollParent = this.targetElement.fastClickScrollParent;
540 }
541
542 targetTagName = targetElement.tagName.toLowerCase();
543 if (targetTagName === 'label') {
544 forElement = this.findControl(targetElement);
545 if (forElement) {
546 this.focus(targetElement);
547 if (deviceIsAndroid) {
548 return false;
549 }
550
551 targetElement = forElement;
552 }
553 } else if (this.needsFocus(targetElement)) {
554
555 // Case 1: If the touch started a while ago (best guess is 100ms based on tests for issue #36) then focus will be triggered anyway. Return early and unset the target element reference so that the subsequent click will be allowed through.
556 // Case 2: Without this exception for input elements tapped when the document is contained in an iframe, then any inputted text won't be visible even though the value attribute is updated as the user types (issue #37).
557 if ((event.timeStamp - trackingClickStart) > 100 || (deviceIsIOS && window.top !== window && targetTagName === 'input')) {
558 this.targetElement = null;
559 return false;
560 }
561
562 this.focus(targetElement);
563 this.sendClick(targetElement, event);
564
565 // Select elements need the event to go through on iOS 4, otherwise the selector menu won't open.
566 // Also this breaks opening selects when VoiceOver is active on iOS6, iOS7 (and possibly others)
567 if (!deviceIsIOS || targetTagName !== 'select') {
568 this.targetElement = null;
569 event.preventDefault();
570 }
571
572 return false;
573 }
574
575 if (deviceIsIOS && !deviceIsIOS4) {
576
577 // Don't send a synthetic click event if the target element is contained within a parent layer that was scrolled
578 // and this tap is being used to stop the scrolling (usually initiated by a fling - issue #42).
579 scrollParent = targetElement.fastClickScrollParent;
580 if (scrollParent && scrollParent.fastClickLastScrollTop !== scrollParent.scrollTop) {
581 return true;
582 }
583 }
584
585 // Prevent the actual click from going though - unless the target node is marked as requiring
586 // real clicks or if it is in the whitelist in which case only non-programmatic clicks are permitted.
587 if (!this.needsClick(targetElement)) {
588 event.preventDefault();
589 this.sendClick(targetElement, event);
590 }
591
592 return false;
593 };
594
595
596 /**
597 * On touch cancel, stop tracking the click.
598 *
599 * @returns {void}
600 */
601 FastClick.prototype.onTouchCancel = function() {
602 this.trackingClick = false;
603 this.targetElement = null;
604 };
605
606
607 /**
608 * Determine mouse events which should be permitted.
609 *
610 * @param {Event} event
611 * @returns {boolean}
612 */
613 FastClick.prototype.onMouse = function(event) {
614
615 // If a target element was never set (because a touch event was never fired) allow the event
616 if (!this.targetElement) {
617 return true;
618 }
619
620 if (event.forwardedTouchEvent) {
621 return true;
622 }
623
624 // Programmatically generated events targeting a specific element should be permitted
625 if (!event.cancelable) {
626 return true;
627 }
628
629 // Derive and check the target element to see whether the mouse event needs to be permitted;
630 // unless explicitly enabled, prevent non-touch click events from triggering actions,
631 // to prevent ghost/doubleclicks.
632 if (!this.needsClick(this.targetElement) || this.cancelNextClick) {
633
634 // Prevent any user-added listeners declared on FastClick element from being fired.
635 if (event.stopImmediatePropagation) {
636 event.stopImmediatePropagation();
637 } else {
638
639 // Part of the hack for browsers that don't support Event#stopImmediatePropagation (e.g. Android 2)
640 event.propagationStopped = true;
641 }
642
643 // Cancel the event
644 event.stopPropagation();
645 event.preventDefault();
646
647 return false;
648 }
649
650 // If the mouse event is permitted, return true for the action to go through.
651 return true;
652 };
653
654
655 /**
656 * On actual clicks, determine whether this is a touch-generated click, a click action occurring
657 * naturally after a delay after a touch (which needs to be cancelled to avoid duplication), or
658 * an actual click which should be permitted.
659 *
660 * @param {Event} event
661 * @returns {boolean}
662 */
663 FastClick.prototype.onClick = function(event) {
664 var permitted;
665
666 // It's possible for another FastClick-like library delivered with third-party code to fire a click event before FastClick does (issue #44). In that case, set the click-tracking flag back to false and return early. This will cause onTouchEnd to return early.
667 if (this.trackingClick) {
668 this.targetElement = null;
669 this.trackingClick = false;
670 return true;
671 }
672
673 // Very odd behaviour on iOS (issue #18): if a submit element is present inside a form and the user hits enter in the iOS simulator or clicks the Go button on the pop-up OS keyboard the a kind of 'fake' click event will be triggered with the submit-type input element as the target.
674 if (event.target.type === 'submit' && event.detail === 0) {
675 return true;
676 }
677
678 permitted = this.onMouse(event);
679
680 // Only unset targetElement if the click is not permitted. This will ensure that the check for !targetElement in onMouse fails and the browser's click doesn't go through.
681 if (!permitted) {
682 this.targetElement = null;
683 }
684
685 // If clicks are permitted, return true for the action to go through.
686 return permitted;
687 };
688
689
690 /**
691 * Remove all FastClick's event listeners.
692 *
693 * @returns {void}
694 */
695 FastClick.prototype.destroy = function() {
696 var layer = this.layer;
697
698 if (deviceIsAndroid) {
699 layer.removeEventListener('mouseover', this.onMouse, true);
700 layer.removeEventListener('mousedown', this.onMouse, true);
701 layer.removeEventListener('mouseup', this.onMouse, true);
702 }
703
704 layer.removeEventListener('click', this.onClick, true);
705 layer.removeEventListener('touchstart', this.onTouchStart, false);
706 layer.removeEventListener('touchmove', this.onTouchMove, false);
707 layer.removeEventListener('touchend', this.onTouchEnd, false);
708 layer.removeEventListener('touchcancel', this.onTouchCancel, false);
709 };
710
711
712 /**
713 * Check whether FastClick is needed.
714 *
715 * @param {Element} layer The layer to listen on
716 */
717 FastClick.notNeeded = function(layer) {
718 var metaViewport;
719 var chromeVersion;
720 var blackberryVersion;
721
722 // Devices that don't support touch don't need FastClick
723 if (typeof window.ontouchstart === 'undefined') {
724 return true;
725 }
726
727 // Chrome version - zero for other browsers
728 chromeVersion = +(/Chrome\/([0-9]+)/.exec(navigator.userAgent) || [,0])[1];
729
730 if (chromeVersion) {
731
732 if (deviceIsAndroid) {
733 metaViewport = document.querySelector('meta[name=viewport]');
734
735 if (metaViewport) {
736 // Chrome on Android with user-scalable="no" doesn't need FastClick (issue #89)
737 if (metaViewport.content.indexOf('user-scalable=no') !== -1) {
738 return true;
739 }
740 // Chrome 32 and above with width=device-width or less don't need FastClick
741 if (chromeVersion > 31 && document.documentElement.scrollWidth <= window.outerWidth) {
742 return true;
743 }
744 }
745
746 // Chrome desktop doesn't need FastClick (issue #15)
747 } else {
748 return true;
749 }
750 }
751
752 if (deviceIsBlackBerry10) {
753 blackberryVersion = navigator.userAgent.match(/Version\/([0-9]*)\.([0-9]*)/);
754
755 // BlackBerry 10.3+ does not require Fastclick library.
756 // https://github.com/ftlabs/fastclick/issues/251
757 if (blackberryVersion[1] >= 10 && blackberryVersion[2] >= 3) {
758 metaViewport = document.querySelector('meta[name=viewport]');
759
760 if (metaViewport) {
761 // user-scalable=no eliminates click delay.
762 if (metaViewport.content.indexOf('user-scalable=no') !== -1) {
763 return true;
764 }
765 // width=device-width (or less than device-width) eliminates click delay.
766 if (document.documentElement.scrollWidth <= window.outerWidth) {
767 return true;
768 }
769 }
770 }
771 }
772
773 // IE10 with -ms-touch-action: none, which disables double-tap-to-zoom (issue #97)
774 if (layer.style.msTouchAction === 'none') {
775 return true;
776 }
777
778 return false;
779 };
780
781
782 /**
783 * Factory method for creating a FastClick object
784 *
785 * @param {Element} layer The layer to listen on
786 * @param {Object} options The options to override the defaults
787 */
788 FastClick.attach = function(layer, options) {
789 return new FastClick(layer, options);
790 };
791
792
793 if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) {
794
795 // AMD. Register as an anonymous module.
796 define(function() {
797 return FastClick;
798 });
799 } else if (typeof module !== 'undefined' && module.exports) {
800 module.exports = FastClick.attach;
801 module.exports.FastClick = FastClick;
802 } else {
803 window.FastClick = FastClick;
804 }
805 }());