实用的 vue tags 创建缓存导航的过程

需求

是要做一个tag，当切换页面的时候保留状态。

思路

既然涉及了router跳转，那我们就去查api 发现 keep-alive ，巧了就用它吧。这里我们用到了 include 属性，该属性接受一个数组，当组件的name名称包含在inclue里的时候就会触发keep-alive。

import { Vue, Component, Watch, Mixins } from 'vue-property-decorator';

...
// 此处省略n行代码

// 这是个计算属性。（至于为什么这么写 这里就不介绍了。）
get cachedViews():string[] {
  return this.$store.state.tagsView.cachedViews;
}

...
// 此处省略n行代码

<keep-alive :include="cachedViews">
  <router-view :key="key"></router-view>
</keep-alive>
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那我们接下来就处理 cachedViews 变量就好了。

vuex实现

import { Route } from 'vue-router';  // 检测规则

interface TagsState{
  visitedViews: Route[];
  cachedViews: string[];
}

const state = (): TagsState => ({
  visitedViews: [], // 展示的菜单
  cachedViews: [], // 缓存菜单 用来activeed
});

const mutations = {
  ADD_VISITED_VIEW: (state: TagsState, view: Route) => {
    if (state.visitedViews.some((v: any) => v.path === view.path)) { return; }
    state.visitedViews.push(
      Object.assign({}, view, {
        title: view.meta.title || 'no-name',
      }),
    );
  },
  ADD_CACHED_VIEW: (state: TagsState, view: Route) => {
    if (state.cachedViews.includes(view.meta.name)) { return; }
    if (!view.meta.noCache) {
      state.cachedViews.push(view.meta.name);
    }
  },

  DEL_VISITED_VIEW: (state: TagsState, view: Route) => {
    for (const [i, v] of state.visitedViews.entries()) {
      if (v.path === view.path) {
        state.visitedViews.splice(i, 1);
        break;
      }
    }
  },
  DEL_CACHED_VIEW: (state: TagsState, view: Route) => {
    const index = state.cachedViews.indexOf(view.meta.name);
    index > -1 && state.cachedViews.splice(index, 1);
  },

  DEL_OTHERS_VISITED_VIEWS: (state: TagsState, view: Route) => {
    state.visitedViews = state.visitedViews.filter((v: any) => {
      return v.meta.affix || v.path === view.path;
    });
  },
  DEL_OTHERS_CACHED_VIEWS: (state: TagsState, view: Route) => {
    const index = state.cachedViews.indexOf(view.meta.name);
    if (index > -1) {
      state.cachedViews = state.cachedViews.slice(index, index + 1);
    } else {
      // if index = -1, there is no cached tags
      state.cachedViews = [];
    }
  },

  DEL_ALL_VISITED_VIEWS: (state: TagsState) => {
    // keep affix tags
    const affixTags = state.visitedViews.filter((tag: any) => tag.meta.affix);
    state.visitedViews = affixTags;
  },
  DEL_ALL_CACHED_VIEWS: (state: TagsState) => {
    state.cachedViews = [];
  },

  UPDATE_VISITED_VIEW: (state: TagsState, view: Route) => {
    for (let v of state.visitedViews) {
      if (v.path === view.path) {
        v = Object.assign(v, view);
        break;
      }
    }
  },
};

const actions = {
  addView({ dispatch }: any, view: Route) {
    dispatch('addVisitedView', view);
    dispatch('addCachedView', view);
  },
  addVisitedView({ commit }: any, view: Route) {
    commit('ADD_VISITED_VIEW', view);
  },
  addCachedView({ commit }: any, view: Route) {
    commit('ADD_CACHED_VIEW', view);
  },

  delView({ dispatch, state }: any, view: Route) {
    return new Promise((resolve) => {
      dispatch('delVisitedView', view);
      dispatch('delCachedView', view);
      resolve({
        visitedViews: [...state.visitedViews],
        cachedViews: [...state.cachedViews],
      });
    });
  },
  delVisitedView({ commit, state }: any, view: Route) {
    return new Promise((resolve) => {
      commit('DEL_VISITED_VIEW', view);
      resolve([...state.visitedViews]);
    });
  },
  delCachedView({ commit, state }: any, view: Route) {
    return new Promise((resolve) => {
      commit('DEL_CACHED_VIEW', view);
      resolve([...state.cachedViews]);
    });
  },

  delOthersViews({ dispatch, state }: any, view: Route) {
    return new Promise((resolve) => {
      dispatch('delOthersVisitedViews', view);
      dispatch('delOthersCachedViews', view);
      resolve({
        visitedViews: [...state.visitedViews],
        cachedViews: [...state.cachedViews],
      });
    });
  },
  delOthersVisitedViews({ commit, state }: any, view: Route) {
    return new Promise((resolve) => {
      commit('DEL_OTHERS_VISITED_VIEWS', view);
      resolve([...state.visitedViews]);
    });
  },
  delOthersCachedViews({ commit, state }: any, view: Route) {
    return new Promise((resolve) => {
      commit('DEL_OTHERS_CACHED_VIEWS', view);
      resolve([...state.cachedViews]);
    });
  },

  delAllViews({ dispatch, state }: any, view: Route) {
    return new Promise((resolve) => {
      dispatch('delAllVisitedViews', view);
      dispatch('delAllCachedViews', view);
      resolve({
        visitedViews: [...state.visitedViews],
        cachedViews: [...state.cachedViews],
      });
    });
  },
  delAllVisitedViews({ commit, state }: any) {
    return new Promise((resolve) => {
      commit('DEL_ALL_VISITED_VIEWS');
      resolve([...state.visitedViews]);
    });
  },
  delAllCachedViews({ commit, state }: any) {
    return new Promise((resolve) => {
      commit('DEL_ALL_CACHED_VIEWS');
      resolve([...state.cachedViews]);
    });
  },

  updateVisitedView({ commit }: any, view: Route) {
    commit('UPDATE_VISITED_VIEW', view);
  },
};

export default {
  namespaced: true,
  state,
  mutations,
  actions,
};

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上面代码，我们定义了一系列的对标签的操作。

组件实现

组件解构如图

TheTagsView.vue

<script lang="ts">
/**
 * @author leo
 * @description #15638 【test_tabs 组件】tab组件
 */
import { Component, Vue, Prop, Watch, Mixins } from 'vue-property-decorator';
import ScrollPane from './ScrollPane.vue';
import path from 'path';

@Component({
  components: {
    ScrollPane,
  },
})
export default class TheTagsView extends Vue {
  get visitedViews() {
    return this.$store.state.tagsView.visitedViews; // 点开过的视图
  }
  get routes() {
    return this.$store.state.permission.routes;
  }

  public visible: boolean = false; // 标签右键列表显示隐藏
  public top: number = 0;   // transform定位
  public left: number = 0;  // transform定位
  public selectedTag: any = {}; // 当前活跃的标签
  public affixTags: any[] = []; // 所有标签

  @Watch('$route')
  public watchRoute() {
    this.addTags();  //  新增当前标签
    this.moveToCurrentTag(); // 删除原活动标签
  }

  @Watch('visible')
  public watchVisible(value: any) {
    if (value) {
        document.body.addEventListener('click', this.closeMenu);
      } else {
        document.body.removeEventListener('click', this.closeMenu);
      }
  }

  public isActive(route: any) {   // 是否当前活动
    return route.path === this.$route.path;
  }

  public isAffix(tag: any) {   // 是否固定
    return tag.meta && tag.meta.affix;
  }

  // 过滤当前标签于路由
  public filterAffixTags(routes: any, basePath = '/') {
    let tags: any = [];
    routes.forEach((route: any) => {
      if (route.meta && route.meta.affix) {
        const tagPath = path.resolve(basePath, route.path);
        tags.push({
          fullPath: tagPath,
          path: tagPath,
          name: route.name,
          meta: { ...route.meta },
        });
      }
      if (route.children) {
        const tempTags = this.filterAffixTags(route.children, route.path);
        if (tempTags.length >= 1) {
          tags = [...tags, ...tempTags];
        }
      }
    });
    return tags;
  }

  public addTags() {
    const { name } = this.$route;
    if (name) {
      this.$store.dispatch('tagsView/addView', this.$route);
    }
    return false;
  }

  public moveToCurrentTag() {
    const tags: any = this.$refs.tag;
    this.$nextTick(() => {
      if (tags) {
        for (const tag of tags) {
          if (tag.to.path === this.$route.path) {
            (this.$refs.scrollPane as any).moveToTarget(tag);
            // when query is different then update
            if (tag.to.fullPath !== this.$route.fullPath) {
              this.$store.dispatch('tagsView/updateVisitedView', this.$route);
            }
            break;
          }
        }
      }
    });
  }
  public refreshSelectedTag(view: any) {
    this.$store.dispatch('tagsView/delCachedView', view).then(() => {
      const { fullPath } = view;
      this.$nextTick(() => {
        this.$router.replace({
          path: '/redirect' + fullPath,
        });
      });
     });
  }

  public closeSelectedTag(view: any) {
    this.$store.dispatch('tagsView/delView', view).then(({ visitedViews }) => {
      if (this.isActive(view)) {
        this.toLastView(visitedViews, view);
      }
    });
  }

  public closeOthersTags() {
    this.$router.push(this.selectedTag);
    this.$store.dispatch('tagsView/delOthersViews', this.selectedTag).then(() => {
      this.moveToCurrentTag();
    });
  }

  public closeAllTags(view: any) {
    this.$store.dispatch('tagsView/delAllViews').then(({ visitedViews }) => {
      if (this.affixTags.some((tag) => tag.path === view.path)) {
        return;
      }
      this.toLastView(visitedViews, view);
    });
  }

  public toLastView(visitedViews: any , view: any) {
    const latestView = visitedViews.slice(-1)[0];
    if (latestView) {
      this.$router.push(latestView.fullPath);
    } else {
      // now the default is to redirect to the home page if there is no tags-view,
      // you can adjust it according to your needs.
      if (view.name === 'Dashboard') {
        // to reload home page
        this.$router.replace({ path: '/redirect' + view.fullPath });
      } else {
        this.$router.push('/');
      }
    }
  }
  public openMenu(tag: any , e: any) {
    const menuMinWidth = 105;
    const offsetLeft = this.$el.getBoundingClientRect().left; // container margin left
    const offsetWidth = this.$el.offsetWidth; // container width
    const maxLeft = offsetWidth - menuMinWidth; // left boundary
    const left = e.clientX - offsetLeft + 15 + 160; // 15: margin right

    if (left > maxLeft) {
      this.left = maxLeft;
    } else {
      this.left = left;
    }

    this.top = e.clientY;
    this.visible = true;
    this.selectedTag = tag;
  }

  public closeMenu() {
    this.visible = false;
  }

  public mounted() {
    this.initTags();
    this.addTags();  // 添加当前页面tag
  }
}
</script>

<template>
  <div id="tags-view-container" class="tags-view-container">
    <scroll-pane ref="scrollPane" class="tags-view-wrapper">
      <router-link
        v-for="(tag, index) in visitedViews"
        ref="tag"
        :key="tag.path"
        :class="isActive(tag)?'active':''"
        :to="{ path: tag.path, query: tag.query, fullPath: tag.fullPath }"
        tag="span"
        class="tags-view-item"
        @click.middle.native="!isAffix(tag)?closeSelectedTag(tag):''"
        @contextmenu.prevent.native="openMenu(tag,$event)"
      >
        {{ tag.title }}
        <!-- <span v-if="!isAffix(tag)" class="el-icon-close" @click.prevent.stop="closeSelectedTag(tag)" /> -->
        <span class="tab-border" v-if="index!==visitedViews.length-1"></span>
      </router-link>
    </scroll-pane>
    <ul v-show="visible" :style="{left:left+'px',top:top+'px'}" class="contextmenu">
      <li @click="refreshSelectedTag(selectedTag)">刷新</li>
      <li v-if="!isAffix(selectedTag)" @click="closeSelectedTag(selectedTag)">关闭当前标签</li>
      <li @click="closeOthersTags">关闭其他标签</li>
      <li @click="closeAllTags(selectedTag)">关闭所有</li>
    </ul>
  </div>
</template>

<style lang="less" scoped>
.tags-view-container {
  height: 46px;
  width: 100%;
  background: #fff;
  .tags-view-wrapper {
    position: relative;
    .tags-view-item {
      display: inline-block;
      position: relative;
      cursor: pointer;
      height: 46px;
      line-height: 46px;
      // border: 1px solid #d8dce5;
      color: #495060;
      background: #fff;
      padding: 0 4px;
      font-size: 14px;
      .tab-border {
        display: inline-block;
        height: 10px;
        width: 1px;
        background: #f1f1f1;
        margin-left: 4px;
      }
      &:hover {
        border-bottom: 2px solid #666;
      }
      &.active {
        // background-color: #1F1A16;
        border-bottom: 2px solid #1F1A16;
        color: #333;
        // border-color: #1F1A16;
        // &::before {
        //   content: '';
        //   background: #fff;
        //   display: inline-block;
        //   width: 8px;
        //   height: 8px;
        //   border-radius: 50%;
        //   position: relative;
        //   margin-right: 2px;
        // }
      }
    }
  }
  .contextmenu {
    margin: 0;
    background: #fff;
    z-index: 3000;
    position: absolute;
    list-style-type: none;
    padding: 5px 0;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 400;
    color: #333;
    box-shadow: 2px 2px 3px 0 rgba(0, 0, 0, .3);
    li {
      margin: 0;
      padding: 7px 16px;
      cursor: pointer;
      &:hover {
        background: #eee;
      }
    }
  }
}
</style>

<style lang="less">
//reset element css of el-icon-close
.tags-view-wrapper {
  .tags-view-item {
    .el-icon-close {
      width: 16px;
      height: 16px;
      vertical-align: 3px;
      border-radius: 50%;
      text-align: center;
      transition: all .3s cubic-bezier(.645, .045, .355, 1);
      transform-origin: 100% 50%;
      &:before {
        transform: scale(.6);
        display: inline-block;
        vertical-align: -3px;
      }
      &:hover {
        background-color: #b4bccc;
        color: #fff;
      }
    }
  }
  .el-scrollbar__bar{
    pointer-events: none;
    opacity: 0;
  }
}
</style>

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ScrollPane.vue

<script lang="ts">
/**
 * @author leo
 * @description #15638 【test_tabs 组件】tab组件
 */
import { Component, Vue, Prop, Watch, Mixins } from 'vue-property-decorator';

const tagAndTagSpacing = 4; // tagAndTagSpacing

@Component({
  components: {
    ScrollPane,
  },
})
export default class ScrollPane extends Vue {
  get scrollWrapper() {
    return (this.$refs.scrollContainer as any).$refs.wrap;
  }

  public left: number = 0;

  public handleScroll(e: any) {
    const eventDelta = e.wheelDelta || -e.deltaY * 40;
    const $scrollWrapper = this.scrollWrapper;
    $scrollWrapper.scrollLeft = $scrollWrapper.scrollLeft + eventDelta / 4;
  }

  public moveToTarget(currentTag: any) {
    const $container = (this.$refs.scrollContainer as any).$el;
    const $containerWidth = $container.offsetWidth;
    const $scrollWrapper = this.scrollWrapper;
    const tagList: any = this.$parent.$refs.tag;

    let firstTag = null;
    let lastTag = null;

    // find first tag and last tag
    if (tagList.length > 0) {
      firstTag = tagList[0];
      lastTag = tagList[tagList.length - 1];
    }

    if (firstTag === currentTag) {
      $scrollWrapper.scrollLeft = 0;
    } else if (lastTag === currentTag) {
      $scrollWrapper.scrollLeft = $scrollWrapper.scrollWidth - $containerWidth;
    } else {
      // find preTag and nextTag
      const currentIndex = tagList.findIndex((item: any) => item === currentTag);
      const prevTag = tagList[currentIndex - 1];
      const nextTag = tagList[currentIndex + 1];

      // the tag's offsetLeft after of nextTag
      const afterNextTagOffsetLeft = nextTag.$el.offsetLeft + nextTag.$el.offsetWidth + tagAndTagSpacing;

      // the tag's offsetLeft before of prevTag
      const beforePrevTagOffsetLeft = prevTag.$el.offsetLeft - tagAndTagSpacing;

      if (afterNextTagOffsetLeft > $scrollWrapper.scrollLeft + $containerWidth) {
        $scrollWrapper.scrollLeft = afterNextTagOffsetLeft - $containerWidth;
      } else if (beforePrevTagOffsetLeft < $scrollWrapper.scrollLeft) {
        $scrollWrapper.scrollLeft = beforePrevTagOffsetLeft;
      }
    }
  }
}
</script>

<template>
  <el-scrollbar ref="scrollContainer" :vertical="false" class="scroll-container" @wheel.native.prevent="handleScroll">
    <slot />
  </el-scrollbar>
</template>

<style lang="less" scoped>
.scroll-container {
  white-space: nowrap;
  position: relative;
  overflow: hidden;
  width: 100%;
  .el-scrollbar__bar {
    bottom: 0px;
  }
  .el-scrollbar__wrap {
    height: 49px;
  }
}
</style>
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index.ts

import TheTagsView from './TheTagsView.vue';
export default TheTagsView;
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这样我们的组件就写完啦，有哪里有问题的小伙伴可以留言哦。

组件调用

因为是全局的，所以放在全局下直接调用就好了 <TheTagsView />

总结

这样我们一个简单的能实现alive 页面的tag功能就实现了。大家赶紧尝试一下吧~

兄台，请留步。这里有几点要注意一下哦~

问题1： 开发环境缓存住了，线上环境不好用了

我们是根据组件name值是否是include里包含的来判断的。但是你会发现生产的的时候 class后面的名在线上被打包后变了。 什么？！这岂不是缓存不住了？？？是的。 所以解决办法如图。一般人我不告诉他0.o

问题2： tags的显示名字我在哪定义呢

tags显示的名字我怎么定义呢，好问题。小兄弟肯定没有仔细读代码

ADD_VISITED_VIEW: (state: TagsState, view: Route) => {
    if (state.visitedViews.some((v: any) => v.path === view.path)) { return; }
    state.visitedViews.push(
      Object.assign({}, view, {
        title: view.meta.title || 'no-name', ///  我在这里！！！！！
      }),
    );
  },
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由上图我们可知，我是在路由的配置里mate标签里的tile里配置的。至于你，随你哦~

{
  	path: 'index', // 入口
    name: 'common-home-index-index',
    component: () => import(/* webpackChunkName: "auth" */ '@/views/home/index.vue'),
    meta: {
        title: '首页', // 看见了么，我就是你要显示的名字
        name: 'CommonHome', // 记住，我要跟你的上面name页面组件名字一样
    },
}
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问题3：我有的页面，跳路由后想刷新了怎么办

那我们页面缓存住了，我怎么让页面刷新呢，比如我新增页面，新增完了需要关闭当前页面跳回列表页面的，我们的思路就是，关闭标签，url 里添加 refresh 参数。

this.$store
            .dispatch('tagsView/delView', this.$route)
            .then(({ visitedViews }) => {
              EventBus.$emit('gotoOwnerDeliveryOrderIndex', {
                refresh: true,
              });
            });	
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然后在 activated 钩子里判断下是否有这个参数。

this.$route.query.refresh && this.fetchData();
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记得处理完结果后 把refresh删了，不然每次进来都刷新了，我们是在拉去数据的混合里删的，因为写一次所有页面都能用。

if ( this.$route.query.refresh ) {
  this.$route.query.refresh = '';
}
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问题4：有没有彩蛋啊

有的，请看图。 我的哥乖乖，怎么实现的呢？

这个留给你们研究吧~ 别麻爪，其实上面代码已经实现了~

只不过你需要再加一个页面和路由。例如刷新功能其实就是跳转到一个新空页面路由。重新跳回来一下~

这里我们定义个跳转视图

redirect/index.vue

<script lang="ts">
import { Component, Vue, Prop, Watch, Mixins } from 'vue-property-decorator';

@Component
export default class Redirect extends Vue {
  public created() {
    const { params, query } = this.$route;
    const { path } = params;
    // debugger;
    this.$router.replace({ path: '/' + path, query });
  }
}
</script>
<template>
</template>
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/**
 * 刷新跳转路由
 */
export const redirectRouter: any = {
  path: '/redirect',
  name: 'redirect',
  component: RouterView,
  children: [
    {
      path: '/redirect/:path*',
      component: () => import(/* webpackChunkName: "redirect" */ '@/views/redirect/index.vue'),
      meta: {
        title: 'title',
      },
    },
  ],
};
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参考

github.com/PanJiaChen/…

---

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我是leo：祝大家早日升职加薪。