element 换主题色 2中方案ExtractTextPlugin和MiniCssExtractPlugin

element 换主题色

1.新建element-variables.scss

/* 改变主题色变量 */
$--color-primary: teal;
 
/* 改变 icon 字体路径变量，必需 */
$--font-path: '~element-ui/lib/theme-chalk/fonts';
 
@import "~element-ui/packages/theme-chalk/src/index";

2。main.js 引入

import './element-variables.scss'

注意：项目依赖于 sass , sass-loader,node-sass 需要安装，不过node-sass已经不维护了，可以只安装sass , sass-loader 不然报错，不过不影响项目运行

sass1.33.0版本以上不支持这种写法,安装对应版本
“sass”: “1.30.0”,
“sass-loader”: “9.0.3”,

补充：webpack全局能使用变量使用插件

安装 “sass-resources-loader”: “^2.2.5”,
ExtractTextPlugin

修改build-utils.js文件

'use strict'
const path = require('path')
const config = require('../config')
const MiniCssExtractPlugin = require('mini-css-extract-plugin')
const packageConfig = require('../package.json')

exports.assetsPath = function(_path) {
  const assetsSubDirectory =
    process.env.NODE_ENV === 'production'
      ? config.build.assetsSubDirectory
      : config.dev.assetsSubDirectory

  return path.posix.join(assetsSubDirectory, _path)
}

exports.cssLoaders = function(options) {
 ...。。。

  // 全局文件引入 当然只想编译一个文件的话可以省去这个函数.  主要是这新增两个方法
  function resolveResource(name) {
    return path.resolve(__dirname, '../src/styles/' + name);
  }
  function generateSassResourceLoader() {
    var loaders = [
      cssLoader,
      'sass-loader',
      {
        loader: 'sass-resources-loader',
        options: {
          // 多个文件时用数组的形式传入，单个文件时可以直接使用 path.resolve(__dirname, '../static/style/common.scss'
          resources: [resolveResource('variables.scss')]
        }
      }
      ];
      if (options.extract) {
        return ExtractTextPlugin.extract({
          use: loaders,
          fallback: 'vue-style-loader'
        })
      } else {
        return ['vue-style-loader'].concat(loaders)
      }
    }
  .....。。。。
  // https://vue-loader.vuejs.org/en/configurations/extract-css.html
  return {
    css: generateLoaders(),
    postcss: generateLoaders(),
    less: generateLoaders('less'),
    sass: generateSassResourceLoader(),
    scss: generateSassResourceLoader(),
    stylus: generateLoaders('stylus'),
    styl: generateLoaders('stylus')
  }
}

使用MiniCssExtractPlugin

'use strict'
const path = require('path')
const config = require('../config')
const MiniCssExtractPlugin = require('mini-css-extract-plugin')
const packageConfig = require('../package.json')
// const ExtractTextPlugin= require('extract-text-webpack-plugin')

exports.assetsPath = function(_path) {
  const assetsSubDirectory =
    process.env.NODE_ENV === 'production'
      ? config.build.assetsSubDirectory
      : config.dev.assetsSubDirectory

  return path.posix.join(assetsSubDirectory, _path)
}

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

  const cssLoader = {
    loader: 'css-loader',
    options: {
      sourceMap: options.sourceMap
    }
  }

  const postcssLoader = {
    loader: 'postcss-loader',
    options: {
      sourceMap: options.sourceMap
    }
  }

  // 全局文件引入 当然只想编译一个文件的话可以省去这个函数
  function resolveResource(name) {
    return path.resolve(__dirname, '../src/styles/' + name);
  }

  // generate loader string to be used with extract text plugin
  function generateLoaders(loader, loaderOptions) {
    const loaders = []

    // Extract CSS when that option is specified
    // (which is the case during production build)
    if (options.extract) {
      loaders.push(MiniCssExtractPlugin.loader)
    } else {
      loaders.push('vue-style-loader')
    }

    loaders.push(cssLoader)

    if (options.usePostCSS) {
      loaders.push(postcssLoader)
    }

    if (loader) {
      if (loader === 'sass-resources') {
        loaders.push({
          loader: 'sass-loader'
        })
      }
      loaders.push({
        loader: loader + '-loader',
        options: Object.assign({}, loaderOptions, {
          sourceMap: options.sourceMap
        })
      })
    }

    return loaders
  }
  // https://vue-loader.vuejs.org/en/configurations/extract-css.html
  return {
    css: generateLoaders(),
    postcss: generateLoaders(),
    less: generateLoaders('less'),
    // sass: generateLoaders('sass', {
    //   indentedSyntax: true
    // }),
    // scss: generateLoaders('sass'),
    sass: generateLoaders('sass-resources', {
      resources: [resolveResource('variables.scss')]
    }),
    scss: generateLoaders('sass-resources', {
      resources: [resolveResource('variables.scss')]
    }),
    stylus: generateLoaders('stylus'),
    styl: generateLoaders('stylus')
  }
}

// Generate loaders for standalone style files (outside of .vue)
exports.styleLoaders = function(options) {
  const output = []
  const loaders = exports.cssLoaders(options)

  for (const extension in loaders) {
    const loader = loaders[extension]
    output.push({
      test: new RegExp('\\.' + extension + '$'),
      use: loader
    })
  }

  return output
}




exports.createNotifierCallback = () => {
  const notifier = require('node-notifier')

  return (severity, errors) => {
    if (severity !== 'error') return

    const error = errors[0]
    const filename = error.file && error.file.split('!').pop()

    notifier.notify({
      title: packageConfig.name,
      message: severity + ': ' + error.name,
      subtitle: filename || '',
      icon: path.join(__dirname, 'logo.png')
    })
  }
}