vue项目页面自适应_lib-flexible_px2rem-loader

一、npm安装依赖

npm i lib-flexible -S

npm i px2rem-loader -D

二、新建文件flexible.js

在src下面新建utils文件夹，并新建一个js文件，取名为flexible.js

(function() {
  // flexible.css
  var cssText =
    '' +
    '@charset "utf-8";html{color:#000;background:#fff;overflow-y:scroll;-webkit-text-size-adjust:100%;-ms-text-size-adjust:100%;-webkit-overflow-scrolling:touch}html *{outline:0;-webkit-text-size-adjust:none;-webkit-tap-highlight-color:transparent}body,html{font-family:"Microsoft YaHei",sans-serif,Tahoma,Arial}article,aside,blockquote,body,button,code,dd,details,div,dl,dt,fieldset,figcaption,figure,footer,form,h1,h2,h3,h4,h5,h6,header,hgroup,hr,input,legend,li,menu,nav,ol,p,pre,section,td,textarea,th,ul{margin:0;padding:0;-webkit-box-sizing:border-box;-moz-box-sizing:border-box;box-sizing:border-box}article,aside,details,figcaption,figure,footer,header,hgroup,menu,nav,section{display:block}input,input[type=button],input[type=reset],input[type=submit]{resize:none;border:none;-webkit-appearance:none;border-radius:0}input,select,textarea{font-size:100%}table{border-collapse:collapse;border-spacing:0}fieldset,img{border:0}abbr,acronym{border:0;font-variant:normal}del{text-decoration:line-through}address,caption,cite,code,dfn,em,th,var{font-style:normal;font-weight:500}ol,ul{list-style:none}caption,th{text-align:left}h1,h2,h3,h4,h5,h6{font-size:100%;font-weight:500}q:after,q:before{content:\'\'}sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline}sup{top:-.5em}sub{bottom:-.25em}a:hover{text-decoration:underline}a,ins{text-decoration:none}a:active,a:hover,a:link,a:visited{background:0 0;-webkit-tap-highlight-color:transparent;-webkit-tap-highlight-color:transparent;outline:0;text-decoration:none}'
  // cssText end
  var styleEl = document.createElement('style')
  document.getElementsByTagName('head')[0].appendChild(styleEl)
  if (styleEl.styleSheet) {
    if (!styleEl.styleSheet.disabled) {
      styleEl.styleSheet.cssText = cssText
    }
  } else {
    try {
      styleEl.innerHTML = cssText
    } catch (e) {
      styleEl.innerText = cssText
    }
  }
})();
(function(win, lib) {
  var doc = win.document
  var docEl = doc.documentElement
  var metaEl = doc.querySelector('meta[name="viewport"]')
  var flexibleEl = doc.querySelector('meta[name="flexible"]')
  var dpr = 0
  var scale = 0
  var tid
  var flexible = lib.flexible || (lib.flexible = {})
  if (metaEl) {
    console.warn('将根据已有的meta标签来设置缩放比例')
    var match = metaEl
      .getAttribute('content')
      .match(/initial\-scale=([\d\.]+)/)
    if (match) {
      scale = parseFloat(match[1])
      dpr = parseInt(1 / scale)
    }
  } else if (flexibleEl) {
    var content = flexibleEl.getAttribute('content')
    if (content) {
      var initialDpr = content.match(/initial\-dpr=([\d\.]+)/)
      var maximumDpr = content.match(/maximum\-dpr=([\d\.]+)/)
      if (initialDpr) {
        dpr = parseFloat(initialDpr[1])
        scale = parseFloat((1 / dpr).toFixed(2))
      }
      if (maximumDpr) {
        dpr = parseFloat(maximumDpr[1])
        scale = parseFloat((1 / dpr).toFixed(2))
      }
    }
  }
  if (!dpr && !scale) {
    // var isAndroid = win.navigator.appVersion.match(/android/gi)
    var isIPhone = win.navigator.appVersion.match(/iphone/gi)
    var devicePixelRatio = win.devicePixelRatio
    if (isIPhone) {
      // iOS下，对于2和3的屏，用2倍的方案，其余的用1倍方案
      if (devicePixelRatio >= 3 && (!dpr || dpr >= 3)) {
        dpr = 3
      } else if (devicePixelRatio >= 2 && (!dpr || dpr >= 2)) {
        dpr = 2
      } else {
        dpr = 1
      }
    } else {
      // 其他设备下，仍旧使用1倍的方案
      dpr = 1
    }
    scale = 1 / dpr
  }
  docEl.setAttribute('data-dpr', dpr)
  if (!metaEl) {
    metaEl = doc.createElement('meta')
    metaEl.setAttribute('name', 'viewport')
    metaEl.setAttribute(
      'content',
      'initial-scale=' +
        scale +
        ', maximum-scale=' +
        scale +
        ', minimum-scale=' +
        scale +
        ', user-scalable=no'
    )
    if (docEl.firstElementChild) {
      docEl.firstElementChild.appendChild(metaEl)
    } else {
      var wrap = doc.createElement('div')
      wrap.appendChild(metaEl)
      doc.write(wrap.innerHTML)
    }
  }
  function refreshRem() {
    var width = docEl.getBoundingClientRect().width
    if (width / dpr > 540) {
      width = width * dpr
    }
    var rem = width / 10
    docEl.style.fontSize = rem + 'px'
    flexible.rem = win.rem = rem
  }
  win.addEventListener(
    'resize',
    function() {
      clearTimeout(tid)
      tid = setTimeout(refreshRem, 300)
    },
    false
  )
  win.addEventListener(
    'pageshow',
    function(e) {
      if (e.persisted) {
        clearTimeout(tid)
        tid = setTimeout(refreshRem, 300)
      }
    },
    false
  )
  if (doc.readyState === 'complete') {
    doc.body.style.fontSize = 12 * dpr + 'px'
  } else {
    doc.addEventListener(
      'DOMContentLoaded',
      function(e) {
        doc.body.style.fontSize = 12 * dpr + 'px'
      },
      false
    )
  }
  refreshRem()
  flexible.dpr = win.dpr = dpr
  flexible.refreshRem = refreshRem
  flexible.rem2px = function(d) {
    var val = parseFloat(d) * this.rem
    if (typeof d === 'string' && d.match(/rem$/)) {
      val += 'px'
    }
    return val
  }
  flexible.px2rem = function(d) {
    var val = parseFloat(d) / this.rem
    if (typeof d === 'string' && d.match(/px$/)) {
      val += 'rem'
    }
    return val
  }
})(window, window['lib'] || (window['lib'] = {}))

然后在main.js中按路径引用

import './utils/flexible'

三、修改build文件夹中的utils.js

exports.cssLoaders = function(options) {
    const px2remLoader = {
        loader: "px2rem-loader",
        options: {
          remUnit: 192
        }
      };

    function generateLoaders(loader, loaderOptions) {
        // const loaders = options.usePostCSS ? [cssLoader, postcssLoader] : [cssLoader];
        const loaders = options.usePostCSS ? [cssLoader, postcssLoader, px2remLoader] : [cssLoader, px2remLoader]
    }
}

四、重启服务，去除页面两侧的滚动条

* {
    margin: 0;
    padding: 0;
}

html {
    width: 100vw;
    height: 100vh;
    overflow-x: hidden;
    overflow-y: hidden !important;
}

注意事项：代码中的px是以flexible.js自动计算成rem的，其中有一个隐藏的问题，就是只能自动转换内嵌的style样式。不能计算行内样式中的px。