git.roojs.org Git - bootswatch/blob - 2/bower_components/bootstrap/docs/assets/js/holder/holder.js

   1 /*
   2
   3 Holder - 1.9 - client side image placeholders
   4 (c) 2012-2013 Ivan Malopinsky / http://imsky.co
   5
   6 Provided under the Apache 2.0 License: http://www.apache.org/licenses/LICENSE-2.0
   7 Commercial use requires attribution.
   8
   9 */
  10
  11 var Holder = Holder || {};
  12 (function (app, win) {
  13
  14 var preempted = false,
  15 fallback = false,
  16 canvas = document.createElement('canvas');
  17
  18 //getElementsByClassName polyfill
  19 document.getElementsByClassName||(document.getElementsByClassName=function(e){var t=document,n,r,i,s=[];if(t.querySelectorAll)return t.querySelectorAll("."+e);if(t.evaluate){r=".//*[contains(concat(' ', @class, ' '), ' "+e+" ')]",n=t.evaluate(r,t,null,0,null);while(i=n.iterateNext())s.push(i)}else{n=t.getElementsByTagName("*"),r=new RegExp("(^|\\s)"+e+"(\\s|$)");for(i=0;i<n.length;i++)r.test(n[i].className)&&s.push(n[i])}return s})
  20
  21 //getComputedStyle polyfill
  22 window.getComputedStyle||(window.getComputedStyle=function(e,t){return this.el=e,this.getPropertyValue=function(t){var n=/(\-([a-z]){1})/g;return t=="float"&&(t="styleFloat"),n.test(t)&&(t=t.replace(n,function(){return arguments[2].toUpperCase()})),e.currentStyle[t]?e.currentStyle[t]:null},this})
  23
  24 //http://javascript.nwbox.com/ContentLoaded by Diego Perini with modifications
  25 function contentLoaded(n,t){var l="complete",s="readystatechange",u=!1,h=u,c=!0,i=n.document,a=i.documentElement,e=i.addEventListener?"addEventListener":"attachEvent",v=i.addEventListener?"removeEventListener":"detachEvent",f=i.addEventListener?"":"on",r=function(e){(e.type!=s||i.readyState==l)&&((e.type=="load"?n:i)[v](f+e.type,r,u),!h&&(h=!0)&&t.call(n,null))},o=function(){try{a.doScroll("left")}catch(n){setTimeout(o,50);return}r("poll")};if(i.readyState==l)t.call(n,"lazy");else{if(i.createEventObject&&a.doScroll){try{c=!n.frameElement}catch(y){}c&&o()}i[e](f+"DOMContentLoaded",r,u),i[e](f+s,r,u),n[e](f+"load",r,u)}};
  26
  27 //https://gist.github.com/991057 by Jed Schmidt with modifications
  28 function selector(a){
  29         a=a.match(/^(\W)?(.*)/);var b=document["getElement"+(a[1]?a[1]=="#"?"ById":"sByClassName":"sByTagName")](a[2]);
  30         var ret=[];     b!=null&&(b.length?ret=b:b.length==0?ret=b:ret=[b]);    return ret;
  31 }
  32
  33 //shallow object property extend
  34 function extend(a,b){var c={};for(var d in a)c[d]=a[d];for(var e in b)c[e]=b[e];return c}
  35
  36 //hasOwnProperty polyfill
  37 if (!Object.prototype.hasOwnProperty)
  38         Object.prototype.hasOwnProperty = function(prop) {
  39                 var proto = this.__proto__ || this.constructor.prototype;
  40                 return (prop in this) && (!(prop in proto) || proto[prop] !== this[prop]);
  41         }
  42
  43 function text_size(width, height, template) {
  44         var dimension_arr = [height, width].sort();
  45         var maxFactor = Math.round(dimension_arr[1] / 16),
  46                 minFactor = Math.round(dimension_arr[0] / 16);
  47         var text_height = Math.max(template.size, maxFactor);
  48         return {
  49                 height: text_height
  50         }
  51 }
  52
  53 function draw(ctx, dimensions, template, ratio) {
  54         var ts = text_size(dimensions.width, dimensions.height, template);
  55         var text_height = ts.height;
  56         var width = dimensions.width * ratio, height = dimensions.height * ratio;
  57         var font = template.font ? template.font : "sans-serif";
  58         canvas.width = width;
  59         canvas.height = height;
  60         ctx.textAlign = "center";
  61         ctx.textBaseline = "middle";
  62         ctx.fillStyle = template.background;
  63         ctx.fillRect(0, 0, width, height);
  64         ctx.fillStyle = template.foreground;
  65         ctx.font = "bold " + text_height + "px "+font;
  66         var text = template.text ? template.text : (dimensions.width + "x" + dimensions.height);
  67         if (ctx.measureText(text).width / width > 1) {
  68                 text_height = template.size / (ctx.measureText(text).width / width);
  69         }
  70         //Resetting font size if necessary
  71         ctx.font = "bold " + (text_height * ratio) + "px "+font;
  72         ctx.fillText(text, (width / 2), (height / 2), width);
  73         return canvas.toDataURL("image/png");
  74 }
  75
  76 function render(mode, el, holder, src) {
  77         var dimensions = holder.dimensions,
  78                 theme = holder.theme,
  79                 text = holder.text ? decodeURIComponent(holder.text) : holder.text;
  80         var dimensions_caption = dimensions.width + "x" + dimensions.height;
  81         theme = (text ? extend(theme, { text: text }) : theme);
  82         theme = (holder.font ? extend(theme, {font: holder.font}) : theme);
  83
  84         var ratio = 1;
  85         if(window.devicePixelRatio && window.devicePixelRatio > 1){
  86                 ratio = window.devicePixelRatio;
  87         }
  88
  89         if (mode == "image") {
  90                 el.setAttribute("data-src", src);
  91                 el.setAttribute("alt", text ? text : theme.text ? theme.text + " [" + dimensions_caption + "]" : dimensions_caption);
  92
  93                 if(fallback || !holder.auto){
  94                     el.style.width = dimensions.width + "px";
  95                     el.style.height = dimensions.height + "px";
  96                 }
  97
  98                 if (fallback) {
  99                         el.style.backgroundColor = theme.background;
 100
 101                 }
 102                 else{
 103                         el.setAttribute("src", draw(ctx, dimensions, theme, ratio));
 104                 }
 105         } else {
 106                 if (!fallback) {
 107                         el.style.backgroundImage = "url(" + draw(ctx, dimensions, theme, ratio) + ")";
 108                         el.style.backgroundSize = dimensions.width+"px "+dimensions.height+"px";
 109                 }
 110         }
 111 };
 112
 113 function fluid(el, holder, src) {
 114         var dimensions = holder.dimensions,
 115                 theme = holder.theme,
 116                 text = holder.text;
 117         var dimensions_caption = dimensions.width + "x" + dimensions.height;
 118         theme = (text ? extend(theme, {
 119                 text: text
 120         }) : theme);
 121
 122         var fluid = document.createElement("div");
 123
 124         fluid.style.backgroundColor = theme.background;
 125         fluid.style.color = theme.foreground;
 126         fluid.className = el.className + " holderjs-fluid";
 127         fluid.style.width = holder.dimensions.width + (holder.dimensions.width.indexOf("%")>0?"":"px");
 128         fluid.style.height = holder.dimensions.height + (holder.dimensions.height.indexOf("%")>0?"":"px");
 129         fluid.id = el.id;
 130
 131         el.style.width=0;
 132         el.style.height=0;
 133
 134         if (theme.text) {
 135                 fluid.appendChild(document.createTextNode(theme.text))
 136         } else {
 137                 fluid.appendChild(document.createTextNode(dimensions_caption))
 138                 fluid_images.push(fluid);
 139                 setTimeout(fluid_update, 0);
 140         }
 141
 142         el.parentNode.insertBefore(fluid, el.nextSibling)
 143
 144         if(window.jQuery){
 145             jQuery(function($){
 146                 $(el).on("load", function(){
 147                    el.style.width = fluid.style.width;
 148                    el.style.height = fluid.style.height;
 149                    $(el).show();
 150                    $(fluid).remove();
 151                 });
 152             })
 153         }
 154 }
 155
 156 function fluid_update() {
 157         for (i in fluid_images) {
 158                 if(!fluid_images.hasOwnProperty(i)) continue;
 159                 var el = fluid_images[i],
 160                         label = el.firstChild;
 161
 162                 el.style.lineHeight = el.offsetHeight+"px";
 163                 label.data = el.offsetWidth + "x" + el.offsetHeight;
 164         }
 165 }
 166
 167 function parse_flags(flags, options) {
 168
 169         var ret = {
 170                 theme: settings.themes.gray
 171         }, render = false;
 172
 173         for (sl = flags.length, j = 0; j < sl; j++) {
 174                 var flag = flags[j];
 175                 if (app.flags.dimensions.match(flag)) {
 176                         render = true;
 177                         ret.dimensions = app.flags.dimensions.output(flag);
 178                 } else if (app.flags.fluid.match(flag)) {
 179                         render = true;
 180                         ret.dimensions = app.flags.fluid.output(flag);
 181                         ret.fluid = true;
 182                 } else if (app.flags.colors.match(flag)) {
 183                         ret.theme = app.flags.colors.output(flag);
 184                 } else if (options.themes[flag]) {
 185                         //If a theme is specified, it will override custom colors
 186                         ret.theme = options.themes[flag];
 187                 } else if (app.flags.text.match(flag)) {
 188                         ret.text = app.flags.text.output(flag);
 189                 } else if(app.flags.font.match(flag)){
 190                         ret.font = app.flags.font.output(flag);
 191                 }
 192                 else if(app.flags.auto.match(flag)){
 193                         ret.auto = true;
 194                 }
 195         }
 196
 197         return render ? ret : false;
 198
 199 };
 200
 201 if (!canvas.getContext) {
 202         fallback = true;
 203 } else {
 204         if (canvas.toDataURL("image/png")
 205                 .indexOf("data:image/png") < 0) {
 206                 //Android doesn't support data URI
 207                 fallback = true;
 208         } else {
 209                 var ctx = canvas.getContext("2d");
 210         }
 211 }
 212
 213 var fluid_images = [];
 214
 215 var settings = {
 216         domain: "holder.js",
 217         images: "img",
 218         bgnodes: ".holderjs",
 219         themes: {
 220                 "gray": {
 221                         background: "#eee",
 222                         foreground: "#aaa",
 223                         size: 12
 224                 },
 225                         "social": {
 226                         background: "#3a5a97",
 227                         foreground: "#fff",
 228                         size: 12
 229                 },
 230                         "industrial": {
 231                         background: "#434A52",
 232                         foreground: "#C2F200",
 233                         size: 12
 234                 }
 235         },
 236         stylesheet: ".holderjs-fluid {font-size:16px;font-weight:bold;text-align:center;font-family:sans-serif;margin:0}"
 237 };
 238
 239
 240 app.flags = {
 241         dimensions: {
 242                 regex: /^(\d+)x(\d+)$/,
 243                 output: function (val) {
 244                         var exec = this.regex.exec(val);
 245                         return {
 246                                 width: +exec[1],
 247                                 height: +exec[2]
 248                         }
 249                 }
 250         },
 251         fluid: {
 252                 regex: /^([0-9%]+)x([0-9%]+)$/,
 253                 output: function (val) {
 254                         var exec = this.regex.exec(val);
 255                         return {
 256                                 width: exec[1],
 257                                 height: exec[2]
 258                         }
 259                 }
 260         },
 261         colors: {
 262                 regex: /#([0-9a-f]{3,})\:#([0-9a-f]{3,})/i,
 263                 output: function (val) {
 264                         var exec = this.regex.exec(val);
 265                         return {
 266                                 size: settings.themes.gray.size,
 267                                 foreground: "#" + exec[2],
 268                                 background: "#" + exec[1]
 269                         }
 270                 }
 271         },
 272         text: {
 273                 regex: /text\:(.*)/,
 274                 output: function (val) {
 275                         return this.regex.exec(val)[1];
 276                 }
 277         },
 278         font: {
 279             regex: /font\:(.*)/,
 280             output: function(val){
 281                 return this.regex.exec(val)[1];
 282             }
 283         },
 284         auto: {
 285             regex: /^auto$/
 286         }
 287 }
 288
 289 for (var flag in app.flags) {
 290         if(!app.flags.hasOwnProperty(flag)) continue;
 291         app.flags[flag].match = function (val) {
 292                 return val.match(this.regex)
 293         }
 294 }
 295
 296 app.add_theme = function (name, theme) {
 297         name != null && theme != null && (settings.themes[name] = theme);
 298         return app;
 299 };
 300
 301 app.add_image = function (src, el) {
 302         var node = selector(el);
 303         if (node.length) {
 304                 for (var i = 0, l = node.length; i < l; i++) {
 305                         var img = document.createElement("img")
 306                         img.setAttribute("data-src", src);
 307                         node[i].appendChild(img);
 308                 }
 309         }
 310         return app;
 311 };
 312
 313 app.run = function (o) {
 314         var options = extend(settings, o), images = [];
 315
 316         if(options.images instanceof window.NodeList){
 317             imageNodes = options.images;
 318         }
 319         else if(options.images instanceof window.Node){
 320             imageNodes = [options.images];
 321         }
 322         else{
 323             imageNodes = selector(options.images);
 324         }
 325
 326         if(options.elements instanceof window.NodeList){
 327             bgnodes = options.bgnodes;
 328         }
 329         else if(options.bgnodes instanceof window.Node){
 330             bgnodes = [options.bgnodes];
 331         }
 332         else{
 333             bgnodes = selector(options.bgnodes);
 334         }
 335
 336         preempted = true;
 337
 338         for (i = 0, l = imageNodes.length; i < l; i++) images.push(imageNodes[i]);
 339
 340         var holdercss = document.getElementById("holderjs-style");
 341
 342         if(!holdercss){
 343             holdercss = document.createElement("style");
 344             holdercss.setAttribute("id", "holderjs-style");
 345             holdercss.type = "text/css";
 346             document.getElementsByTagName("head")[0].appendChild(holdercss);
 347         }
 348
 349         if(holdercss.styleSheet){
 350             holdercss.styleSheet += options.stylesheet;
 351         }
 352         else{
 353             holdercss.textContent+= options.stylesheet;
 354         }
 355
 356         var cssregex = new RegExp(options.domain + "\/(.*?)\"?\\)");
 357
 358         for (var l = bgnodes.length, i = 0; i < l; i++) {
 359                 var src = window.getComputedStyle(bgnodes[i], null)
 360                         .getPropertyValue("background-image");
 361                 var flags = src.match(cssregex);
 362                 if (flags) {
 363                         var holder = parse_flags(flags[1].split("/"), options);
 364                         if (holder) {
 365                                 render("background", bgnodes[i], holder, src);
 366                         }
 367                 }
 368         }
 369
 370         for (var l = images.length, i = 0; i < l; i++) {
 371                 var src = images[i].getAttribute("src") || images[i].getAttribute("data-src");
 372                 if (src != null && src.indexOf(options.domain) >= 0) {
 373                         var holder = parse_flags(src.substr(src.lastIndexOf(options.domain) + options.domain.length + 1)
 374                                 .split("/"), options);
 375                         if (holder) {
 376                                 if (holder.fluid) {
 377                                         fluid(images[i], holder, src);
 378                                 } else {
 379                                         render("image", images[i], holder, src);
 380                                 }
 381                         }
 382                 }
 383         }
 384         return app;
 385 };
 386
 387 contentLoaded(win, function () {
 388         if (window.addEventListener) {
 389                 window.addEventListener("resize", fluid_update, false);
 390                 window.addEventListener("orientationchange", fluid_update, false);
 391         } else {
 392                 window.attachEvent("onresize", fluid_update)
 393         }
 394         preempted || app.run();
 395 });
 396
 397 if ( typeof define === "function" && define.amd ) {
 398         define( "Holder", [], function () { return app; } );
 399 }
 400
 401 })(Holder, window);