Element-ui之ElScrollBar组件滚动条的使用方法

.sidebar {
 position: fixed;
 border-right: 1px solid rgba(0,0,0,.07);
 overflow-y: auto;
 position: absolute;
 top: 0;
 bottom: 0;
 left: 0;
 transition: transform .25s ease-out;
 width: 300px;
 z-index: 3;
}
.sidebar::-webkit-scrollbar {
 width: 4px
}

.sidebar::-webkit-scrollbar-thumb {
 background: transparent;
 border-radius: 4px
}

.sidebar:hover::-webkit-scrollbar-thumb {
 background: hsla(0,0%,53%,.4)
}

.sidebar:hover::-webkit-scrollbar-track {
 background: hsla(0,0%,53%,.1)
}

props: {
 native: Boolean, // 是否使用本地，设为true则不会启用element-ui自定义的滚动条
 wrapStyle: {}, // 包裹层自定义样式
 wrapClass: {}, // 包裹层自定义样式类
 viewClass: {}, // 可滚动部分自定义样式类
 viewStyle: {}, // 可滚动部分自定义样式
 noresize: Boolean, // 如果 container 尺寸不会发生变化，最好设置它可以优化性能
 tag: { // 生成的标签类型，默认使用 `div`标签包裹
  type: String,
  default: 'div'
 }
}

import Scrollbar from './src/main';

/* istanbul ignore next */
Scrollbar.install = function(Vue) {
 Vue.component(Scrollbar.name, Scrollbar);
};

export default Scrollbar;

// reference https://github.com/noeldelgado/gemini-scrollbar/blob/master/index.js

import { addResizeListener, removeResizeListener } from 'element-ui/src/utils/resize-event';
import scrollbarWidth from 'element-ui/src/utils/scrollbar-width';
import { toObject } from 'element-ui/src/utils/util';
import Bar from './bar';

/* istanbul ignore next */
export default {
 name: 'ElScrollbar',

 components: { Bar },

 props: {
 native: Boolean,
 wrapStyle: {},
 wrapClass: {},
 viewClass: {},
 viewStyle: {},
 noresize: Boolean, // 如果 container 尺寸不会发生变化，最好设置它可以优化性能
 tag: {
  type: String,
  default: 'div'
 }
 },

 data() {
 return {
  sizeWidth: '0',
  sizeHeight: '0',
  moveX: 0,
  moveY: 0
 };
 },

 computed: {
 wrap() {
  return this.$refs.wrap;
 }
 },

 render(h) {
 let gutter = scrollbarWidth();
 let style = this.wrapStyle;

 if (gutter) {
  const gutterWith = `-${gutter}px`;
  const gutterStyle = `margin-bottom: ${gutterWith}; margin-right: ${gutterWith};`;

  if (Array.isArray(this.wrapStyle)) {
  style = toObject(this.wrapStyle);
  style.marginRight = style.marginBottom = gutterWith;
  } else if (typeof this.wrapStyle === 'string') {
  style += gutterStyle;
  } else {
  style = gutterStyle;
  }
 }
 const view = h(this.tag, {
  class: ['el-scrollbar__view', this.viewClass],
  style: this.viewStyle,
  ref: 'resize'
 }, this.$slots.default);
 const wrap = (
  

  { [view] }
  
 );
 let nodes;

 if (!this.native) {
  nodes = ([
  wrap,
  ,
  
  ]);
 } else {
  nodes = ([
  

   { [view] }
  
  ]);
 }
 return h('div', { class: 'el-scrollbar' }, nodes);
 },

 methods: {
 handleScroll() {
  const wrap = this.wrap;

  this.moveY = ((wrap.scrollTop * 100) / wrap.clientHeight);
  this.moveX = ((wrap.scrollLeft * 100) / wrap.clientWidth);
 },

 update() {
  let heightPercentage, widthPercentage;
  const wrap = this.wrap;
  if (!wrap) return;

  heightPercentage = (wrap.clientHeight * 100 / wrap.scrollHeight);
  widthPercentage = (wrap.clientWidth * 100 / wrap.scrollWidth);

  this.sizeHeight = (heightPercentage < 100) ? (heightPercentage + '%') : '';
  this.sizeWidth = (widthPercentage < 100) ? (widthPercentage + '%') : '';
 }
 },

 mounted() {
 if (this.native) return;
 this.$nextTick(this.update);
 !this.noresize && addResizeListener(this.$refs.resize, this.update);
 },

 beforeDestroy() {
 if (this.native) return;
 !this.noresize && removeResizeListener(this.$refs.resize, this.update);
 }
};