vue element admin - 侧边栏只显示一个二级菜单

根据文档

在\src\layout\components\Sidebar\index.vue修改

//添加  :unique-opened="true"
<template>
    <div :class="{'has-logo':showLogo}">
        <logo v-if="showLogo" :collapse="isCollapse" />
        <el-scrollbar wrap-class="scrollbar-wrapper">
            <el-menu :default-active="activeMenu" :unique-opened="true" :collapse="isCollapse" :background-color="variables.menuBg" :text-color="variables.menuText" :active-text-color="variables.menuActiveText" :collapse-transition="false" mode="vertical">
                <sidebar-item v-for="route in routes" :key="route.path" :item="route" :base-path="route.path" />
            </el-menu>
        </el-scrollbar>
    </div>
</template>