說說vue-cli中使用flexible和px2rem-loader

摘要： 1.下載lib-flexible npm i lib-flexible --save 或 yarn add lib-flexible 2.在專案中引入lib-flexible 一般情況在(main.js中引入lib-flexible) import 'lib-flexibl...

1.下載lib-flexible

npm i lib-flexible --save
或
yarn add lib-flexible

2.在專案中引入lib-flexible 一般情況在(main.js中引入lib-flexible)

import 'lib-flexible/flexible'

3.設定meta標籤(視情況而定)

<meta name="viewport" content="width=device-width, initial-scale=1.0">

4.安裝px2rem-loader

npm install px2rem-loader--save
或
yarn add px2rem-loader

5.在webpack中配置px2rem-loader

1，在專案build檔案中找到util.js，將px2rem-loader新增到cssLoaders中，

2，px2rem-loader 下的 remUnit 根據設計稿而定

具體如下：

exports.cssLoaders = function (options) {
options = options || {}

const cssLoader = {
loader: 'css-loader',
options: {
minimize: process.env.NODE_ENV === 'production',
sourceMap: options.sourceMap
}
}
//rem編譯（新加px2）
const px2remLoader = {
loader: 'px2rem-loader',
options: {
remUnit: 75 // 由於設計稿是750
}
}

function generateLoaders (loader, loaderOptions) {
var loaders = [cssLoader,px2remLoader]//新增到loader裡面
省略.....
}
}

6.專案中使用

假設設計稿width和font-size分別是200px，50px

具體程式碼：(按照設計稿寫即可)

.demo{
width: 200px;
font-size: 50px;
}

7.單獨使用flexible可直接新增一個rem.js檔案，具體如下：

1，配合less，sass和stylus來做px轉換rem

2，具體可參看css編譯

/*
** 移動端自適應方案FROM 手淘
*/
export const setViewport = (()=>{//此處是單獨使用
const win = window
const lib = window.lib || (window.lib = {})
//;(function(win, lib) {//此處是直接使用
let doc = win.document;
let docEl = doc.documentElement;
let metaEl = doc.querySelector('meta[name="viewport"]');
let flexibleEl = doc.querySelector('meta[name="flexible"]');
let dpr = 0;
let scale = 0;
let tid;
let flexible = lib.flexible || (lib.flexible = {});

if (metaEl) {
//console.warn('將根據已有的meta標籤來設定縮放比例');
let match = metaEl.getAttribute('content').match(/initial\-scale=([\d\.]+)/);
if (match) {
scale = parseFloat(match[1]);
dpr = parseInt(1 / scale);
}
} else if (flexibleEl) {
let content = flexibleEl.getAttribute('content');
if (content) {
let initialDpr = content.match(/initial\-dpr=([\d\.]+)/);
let 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) {
//let isAndroid = win.navigator.appVersion.match(/android/gi);
let isIPhone = win.navigator.appVersion.match(/iphone/gi);
let devicePixelRatio = win.devicePixelRatio;
if (isIPhone) {
// iOS下，對於2和3的屏，用2倍的方案，其餘的用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 {
// 其他裝置下，仍舊使用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 {
let wrap = doc.createElement('div');
wrap.appendChild(metaEl);
doc.write(wrap.innerHTML);
}
}

function refreshRem(){
let width = docEl.getBoundingClientRect().width;
if (width / dpr > 540) {
width = 540 * dpr;
}
let 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() {
doc.body.style.fontSize = 12 * dpr + 'px';
}, false);
}

refreshRem();

flexible.dpr = win.dpr = dpr;
flexible.refreshRem = refreshRem;
flexible.rem2px = function(d) {
let val = parseFloat(d) * this.rem;
if (typeof d === 'string' && d.match(/rem$/)) {
val += 'px';
}
return val;
};
flexible.px2rem = function(d) {
let val = parseFloat(d) / this.rem;
if (typeof d === 'string' && d.match(/px$/)) {
val += 'rem';
}
return val;
};

});
//})(window, window.lib || (window.lib = {}));