PhotoSwipe-一个好用的图片放大缩小插件

通过GitHub 下载PhotoSwipe https://github.com/dimsemenov/PhotoSwipe 相关的库

<link rel="stylesheet" href="css/photoswipe.css" />
<link rel="stylesheet" href="css/default-skin/default-skin.css" />

<script src="js/photoswipe.min.js"></script>
<script src="js/photoswipe-ui-default.js"></script>
<script src="js/connect.js"></script>
//引入相关的css和js文件及皮肤

connect.js

1 document.writeln("<!-- Root element of PhotoSwipe. Must have class pswp. -->");
2 document.writeln("<div class=\"pswp\" tabindex=\"-1\" role=\"dialog\" aria-hidden=\"true\">");
3 document.writeln("");
4 document.writeln("    <!-- Background of PhotoSwipe.");
5 document.writeln("         It\'s a separate element as animating opacity is faster than rgba(). -->");
6 document.writeln("    <div class=\"pswp__bg\"><\/div>");
7 document.writeln("");
8 document.writeln("    <!-- Slides wrapper with overflow:hidden. -->");
9 document.writeln("    <div class=\"pswp__scroll-wrap\">");
10 document.writeln("");
11 document.writeln("        <!-- Container that holds slides.");
12 document.writeln("            PhotoSwipe keeps only 3 of them in the DOM to save memory.");
13 document.writeln("            Don\'t modify these 3 pswp__item elements, data is added later on. -->");
14 document.writeln("        <div class=\"pswp__container\">");
15 document.writeln("            <div class=\"pswp__item\"><\/div>");
16 document.writeln("            <div class=\"pswp__item\"><\/div>");
17 document.writeln("            <div class=\"pswp__item\"><\/div>");
18 document.writeln("        <\/div>");
19 document.writeln("");
20 document.writeln("        <!-- Default (PhotoSwipeUI_Default) interface on top of sliding area. Can be changed. -->");
21 document.writeln("        <div class=\"pswp__ui pswp__ui--hidden\">");
22 document.writeln("");
23 document.writeln("            <div class=\"pswp__top-bar\">");
24 document.writeln("");
25 document.writeln("                <!--  Controls are self-explanatory. Order can be changed. -->");
26 document.writeln("");
27 document.writeln("                <div class=\"pswp__counter\"><\/div>");
28 document.writeln("");
29 document.writeln("                <button class=\"pswp__button pswp__button--close\" title=\"Close (Esc)\"><\/button>");
30 document.writeln("");
31 document.writeln("");
32 document.writeln("                <button class=\"pswp__button pswp__button--fs\" title=\"Toggle fullscreen\"><\/button>");
33 document.writeln("");
34 document.writeln("                <button class=\"pswp__button pswp__button--zoom\" title=\"Zoom in\/out\"><\/button>");
35 document.writeln("");
36 document.writeln("                <!-- Preloader demo http:\/\/codepen.io\/dimsemenov\/pen\/yyBWoR -->");
37 document.writeln("                <!-- element will get class pswp__preloader--active when preloader is running -->");
38 document.writeln("                <div class=\"pswp__preloader\">");
39 document.writeln("                    <div class=\"pswp__preloader__icn\">");
40 document.writeln("                        <div class=\"pswp__preloader__cut\">");
41 document.writeln("                            <div class=\"pswp__preloader__donut\"><\/div>");
42 document.writeln("                        <\/div>");
43 document.writeln("                    <\/div>");
44 document.writeln("                <\/div>");
45 document.writeln("            <\/div>");
46 document.writeln("");
47 document.writeln("            <div class=\"pswp__share-modal pswp__share-modal--hidden pswp__single-tap\">");
48 document.writeln("                <div class=\"pswp__share-tooltip\"><\/div>");
49 document.writeln("            <\/div>");
50 document.writeln("");
51 document.writeln("            <button class=\"pswp__button pswp__button--arrow--left\" title=\"Previous (arrow left)\">");
52 document.writeln("            <\/button>");
53 document.writeln("");
54 document.writeln("            <button class=\"pswp__button pswp__button--arrow--right\" title=\"Next (arrow right)\">");
55 document.writeln("            <\/button>");
56 document.writeln("");
57 document.writeln("            <div class=\"pswp__caption\">");
58 document.writeln("                <div class=\"pswp__caption__center\"><\/div>");
59 document.writeln("            <\/div>");
60 document.writeln("");
61 document.writeln("        <\/div>");
62 document.writeln("");
63 document.writeln("    <\/div>");
64 document.writeln("");
65 document.writeln("<\/div>");
66 //因为作者没有把相关的div放进js里，所以这边通过打印，具体可以观看官方文档得知为什么要这么做。
67     (function() {
68
69     var initPhotoSwipeFromDOM = function(gallerySelector) {
70
71             var parseThumbnailElements = function(el) {
72                 var thumbElements = el.childNodes,
73                     numNodes = thumbElements.length,
74                     items = [],
75                     el,
76                     childElements,
77                     thumbnailEl,
78                     size,
79                     item;
80
81                 for(var i = 0; i < numNodes; i++) {
82                     el = thumbElements[i];
83
84                     // include only element nodes
85                     if(el.nodeType !== 1) {
86                       continue;
87                     }
88
89                     childElements = el.children;
90
91                     size = el.getAttribute('data-size').split('x');
92
93                     // create slide object
94                     item = {
95                         src: el.getAttribute('href'),
96                         w: parseInt(size[0], 10),
97                         h: parseInt(size[1], 10),
98                         author: el.getAttribute('data-author')
99                     };
100
101                     item.el = el; // save link to element for getThumbBoundsFn
102
103                     if(childElements.length > 0) {
104                       item.msrc = childElements[0].getAttribute('src'); // thumbnail url
105                       if(childElements.length > 1) {
106                           item.title = childElements[1].innerHTML; // caption (contents of figure)
107                       }
108                     }
109
110
111                     var mediumSrc = el.getAttribute('data-med');
112                       if(mediumSrc) {
113                         size = el.getAttribute('data-med-size').split('x');
114                         // "medium-sized" image
115                         item.m = {
116                               src: mediumSrc,
117                               w: parseInt(size[0], 10),
118                               h: parseInt(size[1], 10)
119                         };
120                       }
121                       // original image
122                       item.o = {
123                           src: item.src,
124                           w: item.w,
125                           h: item.h
126                       };
127
128                     items.push(item);
129                 }
130
131                 return items;
132             };
133
134             // find nearest parent element
135             var closest = function closest(el, fn) {
136                 return el && ( fn(el) ? el : closest(el.parentNode, fn) );
137             };
138
139             var onThumbnailsClick = function(e) {
140                 e = e || window.event;
141                 e.preventDefault ? e.preventDefault() : e.returnValue = false;
142
143                 var eTarget = e.target || e.srcElement;
144
145                 var clickedListItem = closest(eTarget, function(el) {
146                     return el.tagName === 'A';
147                 });
148
149                 if(!clickedListItem) {
150                     return;
151                 }
152
153                 var clickedGallery = clickedListItem.parentNode;
154
155                 var childNodes = clickedListItem.parentNode.childNodes,
156                     numChildNodes = childNodes.length,
157                     nodeIndex = 0,
158                     index;
159
160                 for (var i = 0; i < numChildNodes; i++) {
161                     if(childNodes[i].nodeType !== 1) {
162                         continue;
163                     }
164
165                     if(childNodes[i] === clickedListItem) {
166                         index = nodeIndex;
167                         break;
168                     }
169                     nodeIndex++;
170                 }
171
172                 if(index >= 0) {
173                     openPhotoSwipe( index, clickedGallery );
174                 }
175                 return false;
176             };
177
178             var photoswipeParseHash = function() {
179                 var hash = window.location.hash.substring(1),
180                 params = {};
181
182                 if(hash.length < 5) { // pid=1
183                     return params;
184                 }
185
186                 var vars = hash.split('&');
187                 for (var i = 0; i < vars.length; i++) {
188                     if(!vars[i]) {
189                         continue;
190                     }
191                     var pair = vars[i].split('=');
192                     if(pair.length < 2) {
193                         continue;
194                     }
195                     params[pair[0]] = pair[1];
196                 }
197
198                 if(params.gid) {
199                     params.gid = parseInt(params.gid, 10);
200                 }
201
202                 return params;
203             };
204
205             var openPhotoSwipe = function(index, galleryElement, disableAnimation, fromURL) {
206                 var pswpElement = document.querySelectorAll('.pswp')[0],
207                     gallery,
208                     options,
209                     items;
210
211                 items = parseThumbnailElements(galleryElement);
212
213                 // define options (if needed)
214                 options = {
215
216                     galleryUID: galleryElement.getAttribute('data-pswp-uid'),
217
218                     getThumbBoundsFn: function(index) {
219                         // See Options->getThumbBoundsFn section of docs for more info
220                         var thumbnail = items[index].el.children[0],
221                             pageYScroll = window.pageYOffset || document.documentElement.scrollTop,
222                             rect = thumbnail.getBoundingClientRect();
223
224                         return {x:rect.left, y:rect.top + pageYScroll, w:rect.width};
225                     },
226
227                     addCaptionHTMLFn: function(item, captionEl, isFake) {
228                         if(!item.title) {
229                             captionEl.children[0].innerText = '';
230                             return false;
231                         }
232                         captionEl.children[0].innerHTML = item.title +  '<br/><small>Photo: ' + item.author + '</small>';
233                         return true;
234                     }
235
236                 };
237
238
239                 if(fromURL) {
240                     if(options.galleryPIDs) {
241                         // parse real index when custom PIDs are used
242                         // http://photoswipe.com/documentation/faq.html#custom-pid-in-url 243                         for(var j = 0; j < items.length; j++) {
244                             if(items[j].pid == index) {
245                                 options.index = j;
246                                 break;
247                             }
248                         }
249                     } else {
250                         options.index = parseInt(index, 10) - 1;
251                     }
252                 } else {
253                     options.index = parseInt(index, 10);
254                 }
255
256                 // exit if index not found
257                 if( isNaN(options.index) ) {
258                     return;
259                 }
260
261
262
263                 var radios = document.getElementsByName('gallery-style');
264                 for (var i = 0, length = radios.length; i < length; i++) {
265                     if (radios[i].checked) {
266                         if(radios[i].id == 'radio-all-controls') {
267
268                         } else if(radios[i].id == 'radio-minimal-black') {
269                             options.mainClass = 'pswp--minimal--dark';
270                             options.barsSize = {top:0,bottom:0};
271                             options.captionEl = false;
272                             options.fullscreenEl = false;
273                             options.shareEl = false;
274                             options.bgOpacity = 0.85;
275                             options.tapToClose = true;
276                             options.tapToToggleControls = false;
277                         }
278                         break;
279                     }
280                 }
281
282                 if(disableAnimation) {
283                     options.showAnimationDuration = 0;
284                 }
285
286                 // Pass data to PhotoSwipe and initialize it
287                 gallery = new PhotoSwipe( pswpElement, PhotoSwipeUI_Default, items, options);
288
289                 // see: http://photoswipe.com/documentation/responsive-images.html 290                 var realViewportWidth,
291                     useLargeImages = false,
292                     firstResize = true,
293                     imageSrcWillChange;
294
295                 gallery.listen('beforeResize', function() {
296
297                     var dpiRatio = window.devicePixelRatio ? window.devicePixelRatio : 1;
298                     dpiRatio = Math.min(dpiRatio, 2.5);
299                     realViewportWidth = gallery.viewportSize.x * dpiRatio;
300
301
302                     if(realViewportWidth >= 1200 || (!gallery.likelyTouchDevice && realViewportWidth > 800) || screen.width > 1200 ) {
303                         if(!useLargeImages) {
304                             useLargeImages = true;
305                             imageSrcWillChange = true;
306                         }
307
308                     } else {
309                         if(useLargeImages) {
310                             useLargeImages = false;
311                             imageSrcWillChange = true;
312                         }
313                     }
314
315                     if(imageSrcWillChange && !firstResize) {
316                         gallery.invalidateCurrItems();
317                     }
318
319                     if(firstResize) {
320                         firstResize = false;
321                     }
322
323                     imageSrcWillChange = false;
324
325                 });
326
327                 gallery.listen('gettingData', function(index, item) {
328                     if( useLargeImages ) {
329                         item.src = item.o.src;
330                         item.w = item.o.w;
331                         item.h = item.o.h;
332                     } else {
333                         item.src = item.m.src;
334                         item.w = item.m.w;
335                         item.h = item.m.h;
336                     }
337                 });
338
339                 gallery.init();
340             };
341
342             // select all gallery elements
343             var galleryElements = document.querySelectorAll( gallerySelector );
344             for(var i = 0, l = galleryElements.length; i < l; i++) {
345                 galleryElements[i].setAttribute('data-pswp-uid', i+1);
346                 galleryElements[i].onclick = onThumbnailsClick;
347             }
348
349             // Parse URL and open gallery if it contains #&pid=3&gid=1
350             var hashData = photoswipeParseHash();
351             if(hashData.pid && hashData.gid) {
352                 openPhotoSwipe( hashData.pid,  galleryElements[ hashData.gid - 1 ], true, true );
353             }
354         };
355
356         initPhotoSwipeFromDOM('.photoswipe');
357
358     })();

我们通过名为photoswipe的class通知要用到的子元素。

a里的图片为放大之后的图片，img里的图片为可实际查看的小图，data-size为要放大的图片大小。

1 <div class="photoswipe">
2     <a href="img/1-max.jpeg" data-size='1000x1000' >
3         <img src="img/1-450.jpeg"/>
4     </a>
5     <a href="http://img3.imgtn.bdimg.com/it/u=4166721891,1503444760&fm=26&gp=0.jpg" data-size='1000x1000' >
6         <img src="http://img3.imgtn.bdimg.com/it/u=4166721891,1503444760&fm=26&gp=0.jpg"/>
7     </a>
8     <a href="http://www.91danji.com/attachments/201511/19/10/24kf5fidw.jpg" data-size='1000x1000' >
9         <img src="http://www.91danji.com/attachments/201511/19/10/24kf5fidw.jpg"/>
10     </a>
11 </div>

拓展：因项目需要，以及通过后台渲染出的图片大小或外链的图片，总不可能一个个设置data-size，于是用jQuery配合js写了几段代码。

1 $(document).ready(function(){ //如果认为代码写的很乱可以自行修改
2     var pic=$("[data-size]");
3     pic.each(function(){
4     var _this = $(this);
5     var images = new Image(); //实例化图片
6     images.src = _this.find('img').attr('src');    //获取小图的链接 进行计算
7     images.onload = function(){  //当图片加载完
8     var tpW = images.width; //图片实际宽度
9     var tpH = images.height //图片实际高度
10     var winW = $(window).width(); //浏览器实际宽度
11     var winH = $(window).height(); //浏览器实际高度
12     var tpRatio = Math.min((winW/tpW),(winH/tpH));
13     var getW = tpW * tpRatio;
14     var getH = tpH * tpRatio; // 屏幕高度 * 图片宽度 / 图片高度
15     _this.attr("data-size",parseInt(getW,10)+"x"+parseInt(getH,10));
16     }
17  });
18 });

该插件是自适应的，具体可以通过谷歌浏览器查看该插件的炫酷之处。