JavaScript

超轻量级php框架startmvc

原生JS实现图片网格式渐显、渐隐效果

更新时间:2020-05-15 18:06 作者:startmvc
先给出效果图:  写的小组件支持图片的渐显、渐隐,并且可以是有序、随机两种方式。

先给出效果图:

  写的小组件支持图片的渐显、渐隐,并且可以是有序、随机两种方式。

  我采用的原型是属性写在构造函数内,方法写在原型对象内。方法写构造函数内有个问题,就是每次调用这个方法就相当于重新实例化一次,举个粟子:

  实现网格效果的原理上是将读取图片的宽高,按照设定的参数,分成等高宽的网格(我用的span标签表示的网格),网格利用定位铺满整个图片,每个网格的背景图都是原图片,原理同sprite,利用background-position属性改变显示区域。接下来就是按照设定的顺序实现渐显或渐隐。渐显或渐隐用的是JS的animation属性和CSS3的animation属性在属性值上有所区别,这次使用也才知道JS的animation属性里有个animationFillMode(规定当动画不播放时(当动画完成时,或当动画有一个延迟未开始播放时),要应用到元素的样式。)属性值。

  我绑定的事件是点击,完全可以用其他事件或页面加载触发。我的代码稍加改动就可以实现网格式轮播图。

  下面给出源代码:


<!doctype html>
<head>
<title>网格效果</title>
<style>
 @charset "utf-8";
 /*css reset*/
 html{font-family:"Helvetica Neue",Helvetica,STHeiTi,sans-serif;-webkit-text-size-adjust:100%;-moz-text-size-adjust:100%;-ms-text-size-adjust:100%;}
 body{-webkit-overflow-scrolling:touch;margin:0;}
 ul{margin:0;padding:0;list-style:none;outline:none;}
 dl,dd{margin:0;}
 a{display:inline-block;margin:0;padding:0;text-decoration:none;background:transparent;outline:none;color:#000;}
 a:link,a:visited,a:hover,a:active{text-decoration:none;color:currentColor;}
 a,dt,dd{-webkit-touch-callout:none;-webkit-tap-highlight-color:transparent;}
 img{border:0;}
 p{margin:0;}
 input,button,select,textarea{margin:0;padding:0;border:0;outline:0;background-color:transparent;}
 /*css*/
 .origin-pic {
 display: inline-block;
 width: 200px;
 height: 200px;
 }
 .grid-area {
 display: inline-block;
 position: relative;
 width: 200px;
 height: 200px;
 }
 .grid {
 position: absolute;
 }
 #img1 {
 opacity: 1;
 width: 200px;
 height: 200px;
 }
 @keyframes fadeout{
 0% {opacity: 1}
 100% {opacity: 0}
 }
 @keyframes fadein{
 0% {opacity: 0}
 100% {opacity: 1}
 }
</style>
</head>
<body>
<div>
 <img class="origin-pic" src="./pic.jpg" />
</div>
<div id="grid_area" class="grid-area">
 <img id="img1" src="./pic.jpg" />
</div>
<script>
var gridSetting = {
 'cell': 10, // 行、列数量
 'mode': 'fadeout', // 备选参数: fadeout, fadein
 'sort': 'random', // 备选参数: inturn, random
 'num': 1, // 每次发生动作的网格数,目前只支持1
 complete: function() { // 事件完成时的回调函数
 console.log('ok!');
 }
};
var img1 = document.getElementById('img1');
(function(doc, setting, ele) {
 var defaults = {
 'speed': 20,
 };
 function Grid(ele) {
 this.ele = ele;
 this.settings = Object.assign({}, setting, defaults);
 }
 Grid.prototype = {
 constructor: Grid,
 // 构建UI
 _create: function() {
 var img = this.ele,
 settings = this.settings,
 cell = settings.cell,
 imgWidth = img.width,
 imgHeight = img.height,
 gridWidth = imgWidth / cell, // 每个网格宽度
 gridHeight = imgHeight / cell, // 每个网格高度
 currentTop = 0,
 currentLeft = 0,
 fragment = doc.createDocumentFragment(),
 i = 0,
 gridArr = [];
 img.style.display = 'none';
 for (; i < cell * cell; i++) {
 var spanNode = doc.createElement('span');
 spanNode.setAttribute('id', i);
 spanNode.style.cssText += 'position: absolute;' +
 'top: ' + currentTop + 'px;' +
 'left: ' + currentLeft + 'px;' +
 'margin: 0;' +
 'padding: 0;' +
 'width: ' + gridWidth + 'px;' +
 'height: ' + gridHeight + 'px;' +
 'opacity:' + settings.opacity + ';' +
 'background: url('+ img.src + ');' +
 'background-size: ' + imgWidth + 'px ' + imgHeight + 'px;' +
 'background-position: -' + currentLeft + 'px -' + currentTop + 'px;';
 if (currentLeft < (imgWidth - gridWidth)) {
 currentLeft += gridWidth;
 } else {
 currentLeft = 0;
 currentTop += gridHeight;
 }
 fragment.append(spanNode);
 gridArr.push(i);
 }
 this.gridArr = gridArr;
 doc.getElementById('grid_area').append(fragment);
 },
 // 渐显、渐隐
 _fade: function() {
 var gridArr = this.gridArr,
 cloneArr = gridArr.slice(0),
 length = gridArr.length,
 settings = this.settings,
 sort = settings.sort,
 i = 0;
 switch(settings.mode) {
 case 'fadeout':
 if (sort == 'inturn') {
 // 按顺序渐隐
 var timer = setInterval(function() {
 doc.getElementById(gridArr[i]).style.animation = "fadeout 1s forwards";
 i++;
 if (i >= settings.cell * settings.cell) {
 clearInterval(timer);
 settings.complete();
 }
 }, settings.speed)
 } else if (sort == 'random') {
 // 随机渐隐
 var timer = setInterval(function() {
 i = cloneArr.splice(Math.random() * length--, 1);
 doc.getElementById(gridArr[i]).style.animation = "fadeout 1s forwards";
 if (length == 0) {
 clearInterval(timer);
 settings.complete();
 }
 }, settings.speed)
 }
 break;
 case 'fadein':
 if (sort == 'inturn') {
 // 按顺序渐渐显
 var timer = setInterval(function() {
 doc.getElementById(gridArr[i]).style.animation = "fadein 1s forwards";
 i++;
 if (i >= settings.cell * settings.cell) {
 clearInterval(timer);
 settings.complete();
 }
 }, settings.speed)
 } else if (sort == 'random') {
 // 随机渐显
 var timer = setInterval(function() {
 i = cloneArr.splice(Math.random() * length--, 1);
 doc.getElementById(gridArr[i]).style.animation = "fadein 1s forwards";
 if (length == 0) {
 clearInterval(timer);
 settings.complete();
 }
 }, settings.speed)
 }
 break;
 default:
 console.log('配置错误!');
 }
 },
 _checkMode: function() {
 if (this.settings.mode == 'fadein') {
 this.settings.opacity = 0;
 } else {
 this.settings.opacity = 1;
 }
 },
 };
 var gridArea = doc.getElementById('grid_area');
 gridArea.addEventListener('click', function() {
 var event = new Grid(ele);
 event._checkMode();
 event._create();
 event._fade();
 }, false);
})(document, gridSetting, img1);
</script>
</body>
</html>

以上所述是小编给大家介绍的原生JS实现图片网格式渐显、渐隐效果,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持!