https://www.fanmaster.com.au/wp-content/plugins/responsive-flipbook/assets/js/jquery.doubletap.js

1(function($) {
2  
3  var defaults = {
4    'swipeTolerance': 40
5  };
6  
7  var touchStatus = function(target, touch) {
8    this.target    = $(target);
9    this.touch     = touch;
10    this.startX    = this.currentX = touch.screenX;
11    this.startY    = this.currentY = touch.screenY;
12    this.eventType = null;
13  }
14  touchStatus.options = {};
15  touchStatus.latestTap = null;
16
17  touchStatus.prototype.move = function(touch) {
18    this.currentX = touch.screenX;
19    this.currentY = touch.screenY;
20  }
21
22  touchStatus.prototype.process = function() {
23    var offsetX = this.currentX - this.startX;
24    var offsetY = this.currentY - this.startY;
25    if(offsetX == 0 && offsetY == 0) {
26      this.checkForDoubleTap();
27    } else if(Math.abs(offsetY) > touchStatus.options.swipeTolerance && Math.abs(offsetY) > Math.abs(offsetX)) {
28      this.eventType = offsetY > 0 ? 'swipedown' : 'swipeup';
29      this.target.trigger('swipe', [this])
30    } else if(Math.abs(offsetX) > touchStatus.options.swipeTolerance) {
31      this.eventType = offsetX > 0 ? 'swiperight' : 'swipeleft';
32      this.target.trigger('swipe', [this])
33    }
34    if(this.eventType) this.target.trigger(this.eventType, [this])
35    this.target.trigger('touch',        [this])
36  }
37
38  touchStatus.prototype.checkForDoubleTap = function() {
39    if(touchStatus.latestTap) {
40      if((new Date() - touchStatus.latestTap) < 400) 
41        this.eventType = 'doubletap'
42    }
43    if(!this.eventType) this.eventType = 'tap'
44    touchStatus.latestTap = new Date()
45  }
46
47  var swipeEvents = function(elements, options) {
48    touchStatus.options = $.extend(defaults, options);
49    elements.bind('touchstart',  this.touchStart);
50    elements.bind('touchmove',   this.touchMove);
51    elements.bind('touchcancel', this.touchCancel);
52    elements.bind('touchend',    this.touchEnd);
53  }
54
55  swipeEvents.prototype.touchStart = function(evt) {
56    var target = this;
57    swipeEvents.eachTouch(evt, function(touch) {
58      swipeEvents.touches[touch.identifier] = new touchStatus(target, touch);
59    })
60  }
61
62  swipeEvents.prototype.touchMove = function(evt) {
63    swipeEvents.eachTouch(evt, function(touch) {
64      var loc = swipeEvents.touches[touch.identifier]
65      if(loc) loc.move(touch)
66    })
67  }
68
69  swipeEvents.prototype.touchCancel = function(evt) {
70    swipeEvents.eachTouch(evt, function(touch) {
71      swipeEvents.purge(touch, true)
72    })
73  }
74
75  swipeEvents.prototype.touchEnd = function(evt) {
76    swipeEvents.eachTouch(evt, function(touch) {
77      swipeEvents.purge(touch)
78    })
79  }
80
81  swipeEvents.touches = {}
82  swipeEvents.purge = function(touch, cancelled) {
83    if(!cancelled) {
84      var loc = swipeEvents.touches[touch.identifier]
85      if(loc) loc.process()
86    }
87    delete swipeEvents.touches[touch.identifier]
88  }
89
90  swipeEvents.eachTouch = function(evt, callback) {
91    var evt = evt.originalEvent;
92    var num = evt.changedTouches.length;
93    for(var i = 0; i < num; i++) {
94      callback(evt.changedTouches[i])
95    }
96  }
97
98  // adds custom events:
99  //   touch      // all events
100  //   swipe      // only swipe* events
101  //   swipeleft
102  //   swiperight
103  //   swipeup
104  //   swipedown
105  //   tap
106  //   doubletap
107  $.fn.addSwipeEvents = function(options, callback) { 
108    if (!callback && jQuery.isFunction(options)) {
109      callback = options;
110      options = null;
111    }
112    new swipeEvents(this, options);
113    if(callback) this.bind('touch', callback);
114    return this;
115  }
116})(jQuery);