- 做者:陈大鱼头
- github: KRISACHAN
进度条是一个很是常见的功能,实现起来也不难,通常咱们都会用 div
来实现。html
做为一个这么常见的需求, whatwg 确定是不会没有原生组件提供(虽然有咱们也不必定会用),那么就让咱们来康康有哪些有意思的进度条实现方式。git
这是比较常规的实现方式,先看效果:github
源码以下:web
<style> .progress1 { height: 20px; width: 300px; background-color: #f5f5f5; border-bottom-right-radius: 10px; border-top-right-radius: 10px; } .progress1::before { counter-reset: progress var(--percent, 0); content: counter(progress) '%\2002'; display: block; height: 20px; line-height: 20px; width: calc(300px * var(--percent, 0) / 100); font-size: 12px; color: #fff; background-color: #2486ff; text-align: right; white-space: nowrap; overflow: hidden; border-bottom-right-radius: 10px; border-top-right-radius: 10px; } .btn { margin-top: 30px; } </style> <div id="progress1" class="progress1"></div> <button id="btn" class="btn">点我一下嘛~</button> <script> 'use strict'; let startTimestamp = (new Date()).getTime(); let currentPercentage = 0; let maxPercentage = 100; let countDelay = 100; let timer = null; let start = false; const percentageChange = () => { const currentTimestamp = (new Date()).getTime(); if (currentTimestamp - startTimestamp >= countDelay) { currentPercentage++; startTimestamp = (new Date()).getTime(); progress1.style = `--percent: ${currentPercentage}`; }; if (currentPercentage < maxPercentage) { timer = window.requestAnimationFrame(percentageChange); } else { window.cancelAnimationFrame(timer); }; }; const clickHander = () => { if (!start) { start = true; percentageChange(); }; }; btn.addEventListener('click', clickHander); </script>
这种方法的核心就是以当前盒子为容器,以 ::before
为内容填充。用 <div>
的好处就是实现简单,兼容性强,拓展性高,可是美中不足的是标签语义化不强。浏览器
<input />
是一个很是实用的替换元素,不一样的 type 能够作不一样的事情。第二种就是用 <input type="range" />
来实现的。首先咱们来看看效果:app
源码以下:ide
<style> .progress2[type='range'] { display: block; font: inherit; height: 20px; width: 300px; pointer-events: none; background-color: linear-gradient(to right, #2376b7 100%, #FFF 0%); } .progress2[type='range'], .progress2[type='range']::-webkit-slider-thumb { -webkit-appearance: none; }; .progress2[type='range']::-webkit-slider-runnable-track { border: none; border-bottom-right-radius: 10px; border-top-right-radius: 10px; height: 20px; width: 300px; } .btn { margin-top: 30px; } </style> <input id="progress2" class="progress2" type='range' step="1" min="0" max="100" value="0"/> <button id="btn" class="btn">点我一下嘛~</button> <script> 'use strict'; let startTimestamp = (new Date()).getTime(); let currentPercentage = 0; let maxPercentage = 100; let countDelay = 100; let timer = null; let start = false; let percentageGap = 10; const percentageChange = () => { const currentTimestamp = (new Date()).getTime(); if (currentTimestamp - startTimestamp >= countDelay) { currentPercentage++; startTimestamp = (new Date()).getTime(); progress2.value = currentPercentage; progress2.style.background = `linear-gradient(to right, #2376b7 ${currentPercentage}%, #FFF 0%`; }; if (currentPercentage < maxPercentage) { timer = window.requestAnimationFrame(percentageChange); } else { window.cancelAnimationFrame(timer); }; }; const clickHander = () => { if (!start) { start = true; percentageChange(); }; }; btn.addEventListener('click', clickHander); </script>
写完这个 demo 才发现,<input type="range" />
并不适合作这个功能。。一个是实现困难,这个 type 组件的每一个元件均可以单独修改样式,可是效果并非很好。spa
另外一个是由于 range 有专属语意 —— 范围,因此它更适合作下面这种事:code
以上demo来自:https://developer.mozilla.org...htm
固然,上述两种方式都是模拟进度条,实际上咱们并不须要模拟,由于 whatwg 有为咱们提供原生的进度条标签 —— <progress>
。
咱们先看效果:
实现以下:
<style> .progress3 { height: 20px; width: 300px; -webkit-appearance: none; display: block; } .progress3::-webkit-progress-value { background: linear-gradient( -45deg, transparent 33%, rgba(0, 0, 0, .1) 33%, rgba(0,0, 0, .1) 66%, transparent 66% ), linear-gradient( to top, rgba(255, 255, 255, .25), rgba(0, 0, 0, .25) ), linear-gradient( to left, #09c, #f44); border-radius: 2px; background-size: 35px 20px, 100% 100%, 100% 100%; } .btn { margin-top: 30px; } </style> <progress id="progress3" class="progress3" max="100" value="0"></progress> <button id="btn" class="btn">点我一下嘛~</button> <script> 'use strict'; let startTimestamp = (new Date()).getTime(); let currentPercentage = 0; let maxPercentage = 100; let countDelay = 100; let timer = null; let start = false; const percentageChange = () => { const currentTimestamp = (new Date()).getTime(); if (currentTimestamp - startTimestamp >= countDelay) { currentPercentage++; startTimestamp = (new Date()).getTime(); progress3.setAttribute('value', currentPercentage); }; if (currentPercentage < maxPercentage) { timer = window.requestAnimationFrame(percentageChange); } else { window.cancelAnimationFrame(timer); }; }; const clickHander = () => { if (!start) { start = true; percentageChange(); }; }; btn.addEventListener('click', clickHander); </script>
虽然有原生的进度条标签,可是规范里并无规定它的具体表现,因此各个浏览器厂商彻底能够按照本身的喜爱去定制,样式彻底不可控,因此标签虽好。。可用性却不强,有点惋惜。
固然,可以实现进度条功能的标签,除了上面所说的,还有 <meter>
标签。先看效果:
代码以下:
<style> .progress4 { display: block; font: inherit; height: 50px; width: 300px; pointer-events: none; } .btn { margin-top: 30px; } </style> <meter id="progress4" class="progress4" low="60" high="80" min="0" max="100" value="0"></meter> <button id="btn" class="btn">点我一下嘛~</button> <script> 'use strict'; let startTimestamp = (new Date()).getTime(); let currentPercentage = 0; let maxPercentage = 100; let countDelay = 100; let timer = null; let start = false; const percentageChange = () => { const currentTimestamp = (new Date()).getTime(); if (currentTimestamp - startTimestamp >= countDelay) { currentPercentage++; startTimestamp = (new Date()).getTime(); progress4.value = currentPercentage; }; if (currentPercentage < maxPercentage) { timer = window.requestAnimationFrame(percentageChange); } else { window.cancelAnimationFrame(timer); }; }; const clickHander = () => { if (!start) { start = true; percentageChange(); }; }; btn.addEventListener('click', clickHander); </script>
这个标签可能比较陌生,实际上它跟 <input type="range">
的语义是同样的,用来显示已知范围的标量值或者分数值。不同的就是。。。它样式改起来更麻烦。
本文测评了4种实现进度条的方式,得出的结论就是 —— <div>
赛高。。。虽然有的时候想优雅一点追求标签语义化,可是资源不支持,也很尴尬。
嗯,万能的 <div>
。
以上 demo 均可以个人 codepen 上查看:https://codepen.io/krischan77...