【JavaScript】spin.js！非常好用，我很喜欢！

  1 /**
  2  * Copyright (c) 2011-2014 Felix Gnass
  3  * Licensed under the MIT license
  4  * http://spin.js.org/
  5  *
  6  * Example:
  7     var opts = {
  8       lines: 12             // The number of lines to draw
  9     , length: 7             // The length of each line
 10     , width: 5              // The line thickness
 11     , radius: 10            // The radius of the inner circle
 12     , scale: 1.0            // Scales overall size of the spinner
 13     , corners: 1            // Roundness (0..1)
 14     , color: ‘#000‘         // #rgb or #rrggbb
 15     , opacity: 1/4          // Opacity of the lines
 16     , rotate: 0             // Rotation offset
 17     , direction: 1          // 1: clockwise, -1: counterclockwise
 18     , speed: 1              // Rounds per second
 19     , trail: 100            // Afterglow percentage
 20     , fps: 20               // Frames per second when using setTimeout()
 21     , zIndex: 2e9           // Use a high z-index by default
 22     , className: ‘spinner‘  // CSS class to assign to the element
 23     , top: ‘50%‘            // center vertically
 24     , left: ‘50%‘           // center horizontally
 25     , shadow: false         // Whether to render a shadow
 26     , hwaccel: false        // Whether to use hardware acceleration (might be buggy)
 27     , position: ‘absolute‘  // Element positioning
 28     }
 29     var target = document.getElementById(‘foo‘)
 30     var spinner = new Spinner(opts).spin(target)
 31  */
 32 ;(function (root, factory) {
 33 
 34   /* CommonJS */
 35   if (typeof module == ‘object‘ && module.exports) module.exports = factory()
 36 
 37   /* AMD module */
 38   else if (typeof define == ‘function‘ && define.amd) define(factory)
 39 
 40   /* Browser global */
 41   else root.Spinner = factory()
 42 }(this, function () {
 43   "use strict"
 44 
 45   var prefixes = [‘webkit‘, ‘Moz‘, ‘ms‘, ‘O‘] /* Vendor prefixes */
 46     , animations = {} /* Animation rules keyed by their name */
 47     , useCssAnimations /* Whether to use CSS animations or setTimeout */
 48     , sheet /* A stylesheet to hold the @keyframe or VML rules. */
 49 
 50   /**
 51    * Utility function to create elements. If no tag name is given,
 52    * a DIV is created. Optionally properties can be passed.
 53    */
 54   function createEl (tag, prop) {
 55     var el = document.createElement(tag || ‘div‘)
 56       , n
 57 
 58     for (n in prop) el[n] = prop[n]
 59     return el
 60   }
 61 
 62   /**
 63    * Appends children and returns the parent.
 64    */
 65   function ins (parent /* child1, child2, ...*/) {
 66     for (var i = 1, n = arguments.length; i < n; i++) {
 67       parent.appendChild(arguments[i])
 68     }
 69 
 70     return parent
 71   }
 72 
 73   /**
 74    * Creates an opacity keyframe animation rule and returns its name.
 75    * Since most mobile Webkits have timing issues with animation-delay,
 76    * we create separate rules for each line/segment.
 77    */
 78   function addAnimation (alpha, trail, i, lines) {
 79     var name = [‘opacity‘, trail, ~~(alpha * 100), i, lines].join(‘-‘)
 80       , start = 0.01 + i/lines * 100
 81       , z = Math.max(1 - (1-alpha) / trail * (100-start), alpha)
 82       , prefix = useCssAnimations.substring(0, useCssAnimations.indexOf(‘Animation‘)).toLowerCase()
 83       , pre = prefix && ‘-‘ + prefix + ‘-‘ || ‘‘
 84 
 85     if (!animations[name]) {
 86       sheet.insertRule(
 87         ‘@‘ + pre + ‘keyframes ‘ + name + ‘{‘ +
 88         ‘0%{opacity:‘ + z + ‘}‘ +
 89         start + ‘%{opacity:‘ + alpha + ‘}‘ +
 90         (start+0.01) + ‘%{opacity:1}‘ +
 91         (start+trail) % 100 + ‘%{opacity:‘ + alpha + ‘}‘ +
 92         ‘100%{opacity:‘ + z + ‘}‘ +
 93         ‘}‘, sheet.cssRules.length)
 94 
 95       animations[name] = 1
 96     }
 97 
 98     return name
 99   }
100 
101   /**
102    * Tries various vendor prefixes and returns the first supported property.
103    */
104   function vendor (el, prop) {
105     var s = el.style
106       , pp
107       , i
108 
109     prop = prop.charAt(0).toUpperCase() + prop.slice(1)
110     if (s[prop] !== undefined) return prop
111     for (i = 0; i < prefixes.length; i++) {
112       pp = prefixes[i]+prop
113       if (s[pp] !== undefined) return pp
114     }
115   }
116 
117   /**
118    * Sets multiple style properties at once.
119    */
120   function css (el, prop) {
121     for (var n in prop) {
122       el.style[vendor(el, n) || n] = prop[n]
123     }
124 
125     return el
126   }
127 
128   /**
129    * Fills in default values.
130    */
131   function merge (obj) {
132     for (var i = 1; i < arguments.length; i++) {
133       var def = arguments[i]
134       for (var n in def) {
135         if (obj[n] === undefined) obj[n] = def[n]
136       }
137     }
138     return obj
139   }
140 
141   /**
142    * Returns the line color from the given string or array.
143    */
144   function getColor (color, idx) {
145     return typeof color == ‘string‘ ? color : color[idx % color.length]
146   }
147 
148   // Built-in defaults
149 
150   var defaults = {
151     lines: 12             // The number of lines to draw
152   , length: 7             // The length of each line
153   , width: 5              // The line thickness
154   , radius: 10            // The radius of the inner circle
155   , scale: 1.0            // Scales overall size of the spinner
156   , corners: 1            // Roundness (0..1)
157   , color: ‘#000‘         // #rgb or #rrggbb
158   , opacity: 1/4          // Opacity of the lines
159   , rotate: 0             // Rotation offset
160   , direction: 1          // 1: clockwise, -1: counterclockwise
161   , speed: 1              // Rounds per second
162   , trail: 100            // Afterglow percentage
163   , fps: 20               // Frames per second when using setTimeout()
164   , zIndex: 2e9           // Use a high z-index by default
165   , className: ‘spinner‘  // CSS class to assign to the element
166   , top: ‘50%‘            // center vertically
167   , left: ‘50%‘           // center horizontally
168   , shadow: false         // Whether to render a shadow
169   , hwaccel: false        // Whether to use hardware acceleration (might be buggy)
170   , position: ‘absolute‘  // Element positioning
171   }
172 
173   /** The constructor */
174   function Spinner (o) {
175     this.opts = merge(o || {}, Spinner.defaults, defaults)
176   }
177 
178   // Global defaults that override the built-ins:
179   Spinner.defaults = {}
180 
181   merge(Spinner.prototype, {
182     /**
183      * Adds the spinner to the given target element. If this instance is already
184      * spinning, it is automatically removed from its previous target b calling
185      * stop() internally.
186      */
187     spin: function (target) {
188       this.stop()
189 
190       var self = this
191         , o = self.opts
192         , el = self.el = createEl(null, {className: o.className})
193 
194       css(el, {
195         position: o.position
196       , width: 0
197       , zIndex: o.zIndex
198       , left: o.left
199       , top: o.top
200       })
201 
202       if (target) {
203         target.insertBefore(el, target.firstChild || null)
204       }
205 
206       el.setAttribute(‘role‘, ‘progressbar‘)
207       self.lines(el, self.opts)
208 
209       if (!useCssAnimations) {
210         // No CSS animation support, use setTimeout() instead
211         var i = 0
212           , start = (o.lines - 1) * (1 - o.direction) / 2
213           , alpha
214           , fps = o.fps
215           , f = fps / o.speed
216           , ostep = (1 - o.opacity) / (f * o.trail / 100)
217           , astep = f / o.lines
218 
219         ;(function anim () {
220           i++
221           for (var j = 0; j < o.lines; j++) {
222             alpha = Math.max(1 - (i + (o.lines - j) * astep) % f * ostep, o.opacity)
223 
224             self.opacity(el, j * o.direction + start, alpha, o)
225           }
226           self.timeout = self.el && setTimeout(anim, ~~(1000 / fps))
227         })()
228       }
229       return self
230     }
231 
232     /**
233      * Stops and removes the Spinner.
234      */
235   , stop: function () {
236       var el = this.el
237       if (el) {
238         clearTimeout(this.timeout)
239         if (el.parentNode) el.parentNode.removeChild(el)
240         this.el = undefined
241       }
242       return this
243     }
244 
245     /**
246      * Internal method that draws the individual lines. Will be overwritten
247      * in VML fallback mode below.
248      */
249   , lines: function (el, o) {
250       var i = 0
251         , start = (o.lines - 1) * (1 - o.direction) / 2
252         , seg
253 
254       function fill (color, shadow) {
255         return css(createEl(), {
256           position: ‘absolute‘
257         , width: o.scale * (o.length + o.width) + ‘px‘
258         , height: o.scale * o.width + ‘px‘
259         , background: color
260         , boxShadow: shadow
261         , transformOrigin: ‘left‘
262         , transform: ‘rotate(‘ + ~~(360/o.lines*i + o.rotate) + ‘deg) translate(‘ + o.scale*o.radius + ‘px‘ + ‘,0)‘
263         , borderRadius: (o.corners * o.scale * o.width >> 1) + ‘px‘
264         })
265       }
266 
267       for (; i < o.lines; i++) {
268         seg = css(createEl(), {
269           position: ‘absolute‘
270         , top: 1 + ~(o.scale * o.width / 2) + ‘px‘
271         , transform: o.hwaccel ? ‘translate3d(0,0,0)‘ : ‘‘
272         , opacity: o.opacity
273         , animation: useCssAnimations && addAnimation(o.opacity, o.trail, start + i * o.direction, o.lines) + ‘ ‘ + 1 / o.speed + ‘s linear infinite‘
274         })
275 
276         if (o.shadow) ins(seg, css(fill(‘#000‘, ‘0 0 4px #000‘), {top: ‘2px‘}))
277         ins(el, ins(seg, fill(getColor(o.color, i), ‘0 0 1px rgba(0,0,0,.1)‘)))
278       }
279       return el
280     }
281 
282     /**
283      * Internal method that adjusts the opacity of a single line.
284      * Will be overwritten in VML fallback mode below.
285      */
286   , opacity: function (el, i, val) {
287       if (i < el.childNodes.length) el.childNodes[i].style.opacity = val
288     }
289 
290   })
291 
292 
293   function initVML () {
294 
295     /* Utility function to create a VML tag */
296     function vml (tag, attr) {
297       return createEl(‘<‘ + tag + ‘ xmlns="urn:schemas-microsoft.com:vml" class="spin-vml">‘, attr)
298     }
299 
300     // No CSS transforms but VML support, add a CSS rule for VML elements:
301     sheet.addRule(‘.spin-vml‘, ‘behavior:url(#default#VML)‘)
302 
303     Spinner.prototype.lines = function (el, o) {
304       var r = o.scale * (o.length + o.width)
305         , s = o.scale * 2 * r
306 
307       function grp () {
308         return css(
309           vml(‘group‘, {
310             coordsize: s + ‘ ‘ + s
311           , coordorigin: -r + ‘ ‘ + -r
312           })
313         , { width: s, height: s }
314         )
315       }
316 
317       var margin = -(o.width + o.length) * o.scale * 2 + ‘px‘
318         , g = css(grp(), {position: ‘absolute‘, top: margin, left: margin})
319         , i
320 
321       function seg (i, dx, filter) {
322         ins(
323           g
324         , ins(
325             css(grp(), {rotation: 360 / o.lines * i + ‘deg‘, left: ~~dx})
326           , ins(
327               css(
328                 vml(‘roundrect‘, {arcsize: o.corners})
329               , { width: r
330                 , height: o.scale * o.width
331                 , left: o.scale * o.radius
332                 , top: -o.scale * o.width >> 1
333                 , filter: filter
334                 }
335               )
336             , vml(‘fill‘, {color: getColor(o.color, i), opacity: o.opacity})
337             , vml(‘stroke‘, {opacity: 0}) // transparent stroke to fix color bleeding upon opacity change
338             )
339           )
340         )
341       }
342 
343       if (o.shadow)
344         for (i = 1; i <= o.lines; i++) {
345           seg(i, -2, ‘progid:DXImageTransform.Microsoft.Blur(pixelradius=2,makeshadow=1,shadowopacity=.3)‘)
346         }
347 
348       for (i = 1; i <= o.lines; i++) seg(i)
349       return ins(el, g)
350     }
351 
352     Spinner.prototype.opacity = function (el, i, val, o) {
353       var c = el.firstChild
354       o = o.shadow && o.lines || 0
355       if (c && i + o < c.childNodes.length) {
356         c = c.childNodes[i + o]; c = c && c.firstChild; c = c && c.firstChild
357         if (c) c.opacity = val
358       }
359     }
360   }
361 
362   if (typeof document !== ‘undefined‘) {
363     sheet = (function () {
364       var el = createEl(‘style‘, {type : ‘text/css‘})
365       ins(document.getElementsByTagName(‘head‘)[0], el)
366       return el.sheet || el.styleSheet
367     }())
368 
369     var probe = css(createEl(‘group‘), {behavior: ‘url(#default#VML)‘})
370 
371     if (!vendor(probe, ‘transform‘) && probe.adj) initVML()
372     else useCssAnimations = vendor(probe, ‘animation‘)
373   }
374 
375   return Spinner
376 
377 }));