holder.js (20260B)
1 /*! 2 3 Holder - 2.3.2 - client side image placeholders 4 (c) 2012-2014 Ivan Malopinsky / http://imsky.co 5 6 Provided under the MIT License. 7 Commercial use requires attribution. 8 9 */ 10 var Holder = Holder || {}; 11 (function (app, win) { 12 var system_config = { 13 use_svg: false, 14 use_canvas: false, 15 use_fallback: false 16 }; 17 var instance_config = {}; 18 var preempted = false; 19 canvas = document.createElement('canvas'); 20 var dpr = 1, bsr = 1; 21 var resizable_images = []; 22 23 if (!canvas.getContext) { 24 system_config.use_fallback = true; 25 } else { 26 if (canvas.toDataURL("image/png") 27 .indexOf("data:image/png") < 0) { 28 //Android doesn't support data URI 29 system_config.use_fallback = true; 30 } else { 31 var ctx = canvas.getContext("2d"); 32 } 33 } 34 35 if(!!document.createElementNS && !!document.createElementNS('http://www.w3.org/2000/svg', 'svg').createSVGRect){ 36 system_config.use_svg = true; 37 system_config.use_canvas = false; 38 } 39 40 if(!system_config.use_fallback){ 41 dpr = window.devicePixelRatio || 1, 42 bsr = ctx.webkitBackingStorePixelRatio || ctx.mozBackingStorePixelRatio || ctx.msBackingStorePixelRatio || ctx.oBackingStorePixelRatio || ctx.backingStorePixelRatio || 1; 43 } 44 45 var ratio = dpr / bsr; 46 47 var settings = { 48 domain: "holder.js", 49 images: "img", 50 bgnodes: ".holderjs", 51 themes: { 52 "gray": { 53 background: "#eee", 54 foreground: "#aaa", 55 size: 12 56 }, 57 "social": { 58 background: "#3a5a97", 59 foreground: "#fff", 60 size: 12 61 }, 62 "industrial": { 63 background: "#434A52", 64 foreground: "#C2F200", 65 size: 12 66 }, 67 "sky": { 68 background: "#0D8FDB", 69 foreground: "#fff", 70 size: 12 71 }, 72 "vine": { 73 background: "#39DBAC", 74 foreground: "#1E292C", 75 size: 12 76 }, 77 "lava": { 78 background: "#F8591A", 79 foreground: "#1C2846", 80 size: 12 81 } 82 }, 83 stylesheet: "" 84 }; 85 app.flags = { 86 dimensions: { 87 regex: /^(\d+)x(\d+)$/, 88 output: function (val) { 89 var exec = this.regex.exec(val); 90 return { 91 width: +exec[1], 92 height: +exec[2] 93 } 94 } 95 }, 96 fluid: { 97 regex: /^([0-9%]+)x([0-9%]+)$/, 98 output: function (val) { 99 var exec = this.regex.exec(val); 100 return { 101 width: exec[1], 102 height: exec[2] 103 } 104 } 105 }, 106 colors: { 107 regex: /#([0-9a-f]{3,})\:#([0-9a-f]{3,})/i, 108 output: function (val) { 109 var exec = this.regex.exec(val); 110 return { 111 size: settings.themes.gray.size, 112 foreground: "#" + exec[2], 113 background: "#" + exec[1] 114 } 115 } 116 }, 117 text: { 118 regex: /text\:(.*)/, 119 output: function (val) { 120 return this.regex.exec(val)[1]; 121 } 122 }, 123 font: { 124 regex: /font\:(.*)/, 125 output: function (val) { 126 return this.regex.exec(val)[1]; 127 } 128 }, 129 auto: { 130 regex: /^auto$/ 131 }, 132 textmode: { 133 regex: /textmode\:(.*)/, 134 output: function(val){ 135 return this.regex.exec(val)[1]; 136 } 137 } 138 } 139 140 function text_size(width, height, template) { 141 height = parseInt(height, 10); 142 width = parseInt(width, 10); 143 var bigSide = Math.max(height, width) 144 var smallSide = Math.min(height, width) 145 var scale = 1 / 12; 146 var newHeight = Math.min(smallSide * 0.75, 0.75 * bigSide * scale); 147 return { 148 height: Math.round(Math.max(template.size, newHeight)) 149 } 150 } 151 152 var svg_el = (function(){ 153 //Prevent IE <9 from initializing SVG renderer 154 if(!window.XMLSerializer) return; 155 var serializer = new XMLSerializer(); 156 var svg_ns = "http://www.w3.org/2000/svg" 157 var svg = document.createElementNS(svg_ns, "svg"); 158 //IE throws an exception if this is set and Chrome requires it to be set 159 if(svg.webkitMatchesSelector){ 160 svg.setAttribute("xmlns", "http://www.w3.org/2000/svg") 161 } 162 var bg_el = document.createElementNS(svg_ns, "rect") 163 var text_el = document.createElementNS(svg_ns, "text") 164 var textnode_el = document.createTextNode(null) 165 text_el.setAttribute("text-anchor", "middle") 166 text_el.appendChild(textnode_el) 167 svg.appendChild(bg_el) 168 svg.appendChild(text_el) 169 170 return function(props){ 171 svg.setAttribute("width",props.width); 172 svg.setAttribute("height", props.height); 173 bg_el.setAttribute("width", props.width); 174 bg_el.setAttribute("height", props.height); 175 bg_el.setAttribute("fill", props.template.background); 176 text_el.setAttribute("x", props.width/2) 177 text_el.setAttribute("y", props.height/2) 178 textnode_el.nodeValue=props.text 179 text_el.setAttribute("style", css_properties({ 180 "fill": props.template.foreground, 181 "font-weight": "bold", 182 "font-size": props.text_height+"px", 183 "font-family":props.font, 184 "dominant-baseline":"central" 185 })) 186 return serializer.serializeToString(svg) 187 } 188 })() 189 190 function css_properties(props){ 191 var ret = []; 192 for(p in props){ 193 if(props.hasOwnProperty(p)){ 194 ret.push(p+":"+props[p]) 195 } 196 } 197 return ret.join(";") 198 } 199 200 function draw_canvas(args) { 201 var ctx = args.ctx, 202 dimensions = args.dimensions, 203 template = args.template, 204 ratio = args.ratio, 205 holder = args.holder, 206 literal = holder.textmode == "literal", 207 exact = holder.textmode == "exact"; 208 209 var ts = text_size(dimensions.width, dimensions.height, template); 210 var text_height = ts.height; 211 var width = dimensions.width * ratio, 212 height = dimensions.height * ratio; 213 var font = template.font ? template.font : "Arial,Helvetica,sans-serif"; 214 canvas.width = width; 215 canvas.height = height; 216 ctx.textAlign = "center"; 217 ctx.textBaseline = "middle"; 218 ctx.fillStyle = template.background; 219 ctx.fillRect(0, 0, width, height); 220 ctx.fillStyle = template.foreground; 221 ctx.font = "bold " + text_height + "px " + font; 222 var text = template.text ? template.text : (Math.floor(dimensions.width) + "x" + Math.floor(dimensions.height)); 223 if (literal) { 224 var dimensions = holder.dimensions; 225 text = dimensions.width + "x" + dimensions.height; 226 } 227 else if(exact && holder.exact_dimensions){ 228 var dimensions = holder.exact_dimensions; 229 text = (Math.floor(dimensions.width) + "x" + Math.floor(dimensions.height)); 230 } 231 var text_width = ctx.measureText(text).width; 232 if (text_width / width >= 0.75) { 233 text_height = Math.floor(text_height * 0.75 * (width / text_width)); 234 } 235 //Resetting font size if necessary 236 ctx.font = "bold " + (text_height * ratio) + "px " + font; 237 ctx.fillText(text, (width / 2), (height / 2), width); 238 return canvas.toDataURL("image/png"); 239 } 240 241 function draw_svg(args){ 242 var dimensions = args.dimensions, 243 template = args.template, 244 holder = args.holder, 245 literal = holder.textmode == "literal", 246 exact = holder.textmode == "exact"; 247 248 var ts = text_size(dimensions.width, dimensions.height, template); 249 var text_height = ts.height; 250 var width = dimensions.width, 251 height = dimensions.height; 252 253 var font = template.font ? template.font : "Arial,Helvetica,sans-serif"; 254 var text = template.text ? template.text : (Math.floor(dimensions.width) + "x" + Math.floor(dimensions.height)); 255 256 if (literal) { 257 var dimensions = holder.dimensions; 258 text = dimensions.width + "x" + dimensions.height; 259 } 260 else if(exact && holder.exact_dimensions){ 261 var dimensions = holder.exact_dimensions; 262 text = (Math.floor(dimensions.width) + "x" + Math.floor(dimensions.height)); 263 } 264 var string = svg_el({ 265 text: text, 266 width:width, 267 height:height, 268 text_height:text_height, 269 font:font, 270 template:template 271 }) 272 return "data:image/svg+xml;base64,"+btoa(unescape(encodeURIComponent(string))); 273 } 274 275 function draw(args) { 276 if(instance_config.use_canvas && !instance_config.use_svg){ 277 return draw_canvas(args); 278 } 279 else{ 280 return draw_svg(args); 281 } 282 } 283 284 function render(mode, el, holder, src) { 285 var dimensions = holder.dimensions, 286 theme = holder.theme, 287 text = holder.text ? decodeURIComponent(holder.text) : holder.text; 288 var dimensions_caption = dimensions.width + "x" + dimensions.height; 289 theme = (text ? extend(theme, { 290 text: text 291 }) : theme); 292 theme = (holder.font ? extend(theme, { 293 font: holder.font 294 }) : theme); 295 el.setAttribute("data-src", src); 296 holder.theme = theme; 297 el.holder_data = holder; 298 299 if (mode == "image") { 300 el.setAttribute("alt", text ? text : theme.text ? theme.text + " [" + dimensions_caption + "]" : dimensions_caption); 301 if (instance_config.use_fallback || !holder.auto) { 302 el.style.width = dimensions.width + "px"; 303 el.style.height = dimensions.height + "px"; 304 } 305 if (instance_config.use_fallback) { 306 el.style.backgroundColor = theme.background; 307 } else { 308 el.setAttribute("src", draw({ctx: ctx, dimensions: dimensions, template: theme, ratio:ratio, holder: holder})); 309 310 if(holder.textmode && holder.textmode == "exact"){ 311 resizable_images.push(el); 312 resizable_update(el); 313 } 314 315 } 316 } else if (mode == "background") { 317 if (!instance_config.use_fallback) { 318 el.style.backgroundImage = "url(" + draw({ctx:ctx, dimensions: dimensions, template: theme, ratio: ratio, holder: holder}) + ")"; 319 el.style.backgroundSize = dimensions.width + "px " + dimensions.height + "px"; 320 } 321 } else if (mode == "fluid") { 322 el.setAttribute("alt", text ? text : theme.text ? theme.text + " [" + dimensions_caption + "]" : dimensions_caption); 323 if (dimensions.height.slice(-1) == "%") { 324 el.style.height = dimensions.height 325 } else if(holder.auto == null || !holder.auto){ 326 el.style.height = dimensions.height + "px" 327 } 328 if (dimensions.width.slice(-1) == "%") { 329 el.style.width = dimensions.width 330 } else if(holder.auto == null || !holder.auto){ 331 el.style.width = dimensions.width + "px" 332 } 333 if (el.style.display == "inline" || el.style.display === "" || el.style.display == "none") { 334 el.style.display = "block"; 335 } 336 337 set_initial_dimensions(el) 338 339 if (instance_config.use_fallback) { 340 el.style.backgroundColor = theme.background; 341 } else { 342 resizable_images.push(el); 343 resizable_update(el); 344 } 345 } 346 } 347 348 function dimension_check(el, callback) { 349 var dimensions = { 350 height: el.clientHeight, 351 width: el.clientWidth 352 }; 353 if (!dimensions.height && !dimensions.width) { 354 el.setAttribute("data-holder-invisible", true) 355 callback.call(this, el) 356 } 357 else{ 358 el.removeAttribute("data-holder-invisible") 359 return dimensions; 360 } 361 } 362 363 function set_initial_dimensions(el){ 364 if(el.holder_data){ 365 var dimensions = dimension_check(el, app.invisible_error_fn( set_initial_dimensions)) 366 if(dimensions){ 367 var holder = el.holder_data; 368 holder.initial_dimensions = dimensions; 369 holder.fluid_data = { 370 fluid_height: holder.dimensions.height.slice(-1) == "%", 371 fluid_width: holder.dimensions.width.slice(-1) == "%", 372 mode: null 373 } 374 if(holder.fluid_data.fluid_width && !holder.fluid_data.fluid_height){ 375 holder.fluid_data.mode = "width" 376 holder.fluid_data.ratio = holder.initial_dimensions.width / parseFloat(holder.dimensions.height) 377 } 378 else if(!holder.fluid_data.fluid_width && holder.fluid_data.fluid_height){ 379 holder.fluid_data.mode = "height"; 380 holder.fluid_data.ratio = parseFloat(holder.dimensions.width) / holder.initial_dimensions.height 381 } 382 } 383 } 384 } 385 386 function resizable_update(element) { 387 var images; 388 if (element.nodeType == null) { 389 images = resizable_images; 390 } else { 391 images = [element] 392 } 393 for (var i in images) { 394 if (!images.hasOwnProperty(i)) { 395 continue; 396 } 397 var el = images[i] 398 if (el.holder_data) { 399 var holder = el.holder_data; 400 var dimensions = dimension_check(el, app.invisible_error_fn( resizable_update)) 401 if(dimensions){ 402 if(holder.fluid){ 403 if(holder.auto){ 404 switch(holder.fluid_data.mode){ 405 case "width": 406 dimensions.height = dimensions.width / holder.fluid_data.ratio; 407 break; 408 case "height": 409 dimensions.width = dimensions.height * holder.fluid_data.ratio; 410 break; 411 } 412 } 413 el.setAttribute("src", draw({ 414 ctx: ctx, 415 dimensions: dimensions, 416 template: holder.theme, 417 ratio: ratio, 418 holder: holder 419 })) 420 } 421 if(holder.textmode && holder.textmode == "exact"){ 422 holder.exact_dimensions = dimensions; 423 el.setAttribute("src", draw({ 424 ctx: ctx, 425 dimensions: holder.dimensions, 426 template: holder.theme, 427 ratio: ratio, 428 holder: holder 429 })) 430 } 431 } 432 } 433 } 434 } 435 436 function parse_flags(flags, options) { 437 var ret = { 438 theme: extend(settings.themes.gray, {}) 439 }; 440 var render = false; 441 for (var fl = flags.length, j = 0; j < fl; j++) { 442 var flag = flags[j]; 443 if (app.flags.dimensions.match(flag)) { 444 render = true; 445 ret.dimensions = app.flags.dimensions.output(flag); 446 } else if (app.flags.fluid.match(flag)) { 447 render = true; 448 ret.dimensions = app.flags.fluid.output(flag); 449 ret.fluid = true; 450 } else if (app.flags.textmode.match(flag)) { 451 ret.textmode = app.flags.textmode.output(flag) 452 } else if (app.flags.colors.match(flag)) { 453 ret.theme = app.flags.colors.output(flag); 454 } else if (options.themes[flag]) { 455 //If a theme is specified, it will override custom colors 456 if(options.themes.hasOwnProperty(flag)){ 457 ret.theme = extend(options.themes[flag], {}); 458 } 459 } else if (app.flags.font.match(flag)) { 460 ret.font = app.flags.font.output(flag); 461 } else if (app.flags.auto.match(flag)) { 462 ret.auto = true; 463 } else if (app.flags.text.match(flag)) { 464 ret.text = app.flags.text.output(flag); 465 } 466 } 467 return render ? ret : false; 468 } 469 470 for (var flag in app.flags) { 471 if (!app.flags.hasOwnProperty(flag)) continue; 472 app.flags[flag].match = function (val) { 473 return val.match(this.regex) 474 } 475 } 476 477 app.invisible_error_fn = function(fn){ 478 return function(el){ 479 if(el.hasAttribute("data-holder-invisible")){ 480 throw new Error("Holder: invisible placeholder") 481 } 482 } 483 } 484 485 app.add_theme = function (name, theme) { 486 name != null && theme != null && (settings.themes[name] = theme); 487 return app; 488 }; 489 490 app.add_image = function (src, el) { 491 var node = selector(el); 492 if (node.length) { 493 for (var i = 0, l = node.length; i < l; i++) { 494 var img = document.createElement("img") 495 img.setAttribute("data-src", src); 496 node[i].appendChild(img); 497 } 498 } 499 return app; 500 }; 501 502 app.run = function (o) { 503 504 instance_config = extend({}, system_config) 505 preempted = true; 506 507 var options = extend(settings, o), 508 images = [], 509 imageNodes = [], 510 bgnodes = []; 511 512 if(options.use_canvas != null && options.use_canvas){ 513 instance_config.use_canvas = true; 514 instance_config.use_svg = false; 515 } 516 517 if (typeof (options.images) == "string") { 518 imageNodes = selector(options.images); 519 } else if (window.NodeList && options.images instanceof window.NodeList) { 520 imageNodes = options.images; 521 } else if (window.Node && options.images instanceof window.Node) { 522 imageNodes = [options.images]; 523 } else if(window.HTMLCollection && options.images instanceof window.HTMLCollection){ 524 imageNodes = options.images 525 } 526 527 if (typeof (options.bgnodes) == "string") { 528 bgnodes = selector(options.bgnodes); 529 } else if (window.NodeList && options.elements instanceof window.NodeList) { 530 bgnodes = options.bgnodes; 531 } else if (window.Node && options.bgnodes instanceof window.Node) { 532 bgnodes = [options.bgnodes]; 533 } 534 for (i = 0, l = imageNodes.length; i < l; i++) images.push(imageNodes[i]); 535 536 var holdercss = document.getElementById("holderjs-style"); 537 if (!holdercss) { 538 holdercss = document.createElement("style"); 539 holdercss.setAttribute("id", "holderjs-style"); 540 holdercss.type = "text/css"; 541 document.getElementsByTagName("head")[0].appendChild(holdercss); 542 } 543 544 if (!options.nocss) { 545 if (holdercss.styleSheet) { 546 holdercss.styleSheet.cssText += options.stylesheet; 547 } else { 548 if(options.stylesheet.length){ 549 holdercss.appendChild(document.createTextNode(options.stylesheet)); 550 } 551 } 552 } 553 554 var cssregex = new RegExp(options.domain + "\/(.*?)\"?\\)"); 555 for (var l = bgnodes.length, i = 0; i < l; i++) { 556 var src = window.getComputedStyle(bgnodes[i], null) 557 .getPropertyValue("background-image"); 558 var flags = src.match(cssregex); 559 var bgsrc = bgnodes[i].getAttribute("data-background-src"); 560 if (flags) { 561 var holder = parse_flags(flags[1].split("/"), options); 562 if (holder) { 563 render("background", bgnodes[i], holder, src); 564 } 565 } else if (bgsrc != null) { 566 var holder = parse_flags(bgsrc.substr(bgsrc.lastIndexOf(options.domain) + options.domain.length + 1) 567 .split("/"), options); 568 if (holder) { 569 render("background", bgnodes[i], holder, src); 570 } 571 } 572 } 573 for (l = images.length, i = 0; i < l; i++) { 574 var attr_data_src, attr_src; 575 attr_src = attr_data_src = src = null; 576 try { 577 attr_src = images[i].getAttribute("src"); 578 attr_datasrc = images[i].getAttribute("data-src"); 579 } catch (e) {} 580 if (attr_datasrc == null && !! attr_src && attr_src.indexOf(options.domain) >= 0) { 581 src = attr_src; 582 } else if ( !! attr_datasrc && attr_datasrc.indexOf(options.domain) >= 0) { 583 src = attr_datasrc; 584 } 585 if (src) { 586 var holder = parse_flags(src.substr(src.lastIndexOf(options.domain) + options.domain.length + 1).split("/"), options); 587 if (holder) { 588 if (holder.fluid) { 589 render("fluid", images[i], holder, src) 590 } else { 591 render("image", images[i], holder, src); 592 } 593 } 594 } 595 } 596 return app; 597 }; 598 599 contentLoaded(win, function () { 600 if (window.addEventListener) { 601 window.addEventListener("resize", resizable_update, false); 602 window.addEventListener("orientationchange", resizable_update, false); 603 } else { 604 window.attachEvent("onresize", resizable_update) 605 } 606 preempted || app.run({}); 607 608 if (typeof window.Turbolinks === "object") { 609 document.addEventListener("page:change", function() { app.run({}) }) 610 } 611 }); 612 if (typeof define === "function" && define.amd) { 613 define([], function () { 614 return app; 615 }); 616 } 617 618 //github.com/davidchambers/Base64.js 619 (function(){function t(t){this.message=t}var e="undefined"!=typeof exports?exports:this,r="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";t.prototype=Error(),t.prototype.name="InvalidCharacterError",e.btoa||(e.btoa=function(e){for(var o,n,a=0,i=r,c="";e.charAt(0|a)||(i="=",a%1);c+=i.charAt(63&o>>8-8*(a%1))){if(n=e.charCodeAt(a+=.75),n>255)throw new t("'btoa' failed");o=o<<8|n}return c}),e.atob||(e.atob=function(e){if(e=e.replace(/=+$/,""),1==e.length%4)throw new t("'atob' failed");for(var o,n,a=0,i=0,c="";n=e.charAt(i++);~n&&(o=a%4?64*o+n:n,a++%4)?c+=String.fromCharCode(255&o>>(6&-2*a)):0)n=r.indexOf(n);return c})})(); 620 621 //getElementsByClassName polyfill 622 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}) 623 624 //getComputedStyle polyfill 625 window.getComputedStyle||(window.getComputedStyle=function(e){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}) 626 627 //http://javascript.nwbox.com/ContentLoaded by Diego Perini with modifications 628 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)}} 629 630 //https://gist.github.com/991057 by Jed Schmidt with modifications 631 function selector(a,b){var a=a.match(/^(\W)?(.*)/),b=b||document,c=b["getElement"+(a[1]?"#"==a[1]?"ById":"sByClassName":"sByTagName")],d=c.call(b,a[2]),e=[];return null!==d&&(e=d.length||0===d.length?d:[d]),e} 632 633 //shallow object property extend 634 function extend(a,b){ 635 var c={}; 636 for(var i in a){ 637 if(a.hasOwnProperty(i)){ 638 c[i]=a[i]; 639 } 640 } 641 for(var i in b){ 642 if(b.hasOwnProperty(i)){ 643 c[i]=b[i]; 644 } 645 } 646 return c 647 } 648 649 //hasOwnProperty polyfill 650 if (!Object.prototype.hasOwnProperty) 651 /*jshint -W001, -W103 */ 652 Object.prototype.hasOwnProperty = function(prop) { 653 var proto = this.__proto__ || this.constructor.prototype; 654 return (prop in this) && (!(prop in proto) || proto[prop] !== this[prop]); 655 } 656 /*jshint +W001, +W103 */ 657 658 })(Holder, window);