ElementUI浅尝辄止32：NavMenu 导航菜单

为网站提供导航功能的菜单。常用于网站平台顶部或侧边栏菜单导航。

1.如何使用？顶栏

/*导航菜单默认为垂直模式，通过mode属性可以使导航菜单变更为水平模式。另外，在菜单中通过submenu组件可以生成二级菜单。Menu 还提供了background-color、text-color和active-text-color，分别用于设置菜单的背景色、菜单的文字颜色和当前激活菜单的文字颜色。*/

<el-menu :default-active="activeIndex" class="el-menu-demo" mode="horizontal" @select="handleSelect">
  <el-menu-item index="1">处理中心</el-menu-item>
  <el-submenu index="2">
    <template slot="title">我的工作台</template>
    <el-menu-item index="2-1">选项1</el-menu-item>
    <el-menu-item index="2-2">选项2</el-menu-item>
    <el-menu-item index="2-3">选项3</el-menu-item>
    <el-submenu index="2-4">
      <template slot="title">选项4</template>
      <el-menu-item index="2-4-1">选项1</el-menu-item>
      <el-menu-item index="2-4-2">选项2</el-menu-item>
      <el-menu-item index="2-4-3">选项3</el-menu-item>
    </el-submenu>
  </el-submenu>
  <el-menu-item index="3" disabled>消息中心</el-menu-item>
  <el-menu-item index="4"><a href="https://www.ele.me" target="_blank">订单管理</a></el-menu-item>
</el-menu>
<div class="line"></div>
<el-menu
  :default-active="activeIndex2"
  class="el-menu-demo"
  mode="horizontal"
  @select="handleSelect"
  background-color="#545c64"
  text-color="#fff"
  active-text-color="#ffd04b">
  <el-menu-item index="1">处理中心</el-menu-item>
  <el-submenu index="2">
    <template slot="title">我的工作台</template>
    <el-menu-item index="2-1">选项1</el-menu-item>
    <el-menu-item index="2-2">选项2</el-menu-item>
    <el-menu-item index="2-3">选项3</el-menu-item>
    <el-submenu index="2-4">
      <template slot="title">选项4</template>
      <el-menu-item index="2-4-1">选项1</el-menu-item>
      <el-menu-item index="2-4-2">选项2</el-menu-item>
      <el-menu-item index="2-4-3">选项3</el-menu-item>
    </el-submenu>
  </el-submenu>
  <el-menu-item index="3" disabled>消息中心</el-menu-item>
  <el-menu-item index="4"><a href="https://www.ele.me" target="_blank">订单管理</a></el-menu-item>
</el-menu>

<script>
  export default {
    data() {
      return {
        activeIndex: '1',
        activeIndex2: '1'
      };
    },
    methods: {
      handleSelect(key, keyPath) {
        console.log(key, keyPath);
      }
    }
  }
</script>

2.侧栏

垂直菜单，可内嵌子菜单。

//通过el-menu-item-group组件可以实现菜单进行分组，分组名可以通过title属性直接设定，也可以通过具名 slot 来设定。

<el-row class="tac">
  <el-col :span="12">
    <h5>默认颜色</h5>
    <el-menu
      default-active="2"
      class="el-menu-vertical-demo"
      @open="handleOpen"
      @close="handleClose">
      <el-submenu index="1">
        <template slot="title">
          <i class="el-icon-location"></i>
          <span>导航一</span>
        </template>
        <el-menu-item-group>
          <template slot="title">分组一</template>
          <el-menu-item index="1-1">选项1</el-menu-item>
          <el-menu-item index="1-2">选项2</el-menu-item>
        </el-menu-item-group>
        <el-menu-item-group title="分组2">
          <el-menu-item index="1-3">选项3</el-menu-item>
        </el-menu-item-group>
        <el-submenu index="1-4">
          <template slot="title">选项4</template>
          <el-menu-item index="1-4-1">选项1</el-menu-item>
        </el-submenu>
      </el-submenu>
      <el-menu-item index="2">
        <i class="el-icon-menu"></i>
        <span slot="title">导航二</span>
      </el-menu-item>
      <el-menu-item index="3" disabled>
        <i class="el-icon-document"></i>
        <span slot="title">导航三</span>
      </el-menu-item>
      <el-menu-item index="4">
        <i class="el-icon-setting"></i>
        <span slot="title">导航四</span>
      </el-menu-item>
    </el-menu>
  </el-col>
  <el-col :span="12">
    <h5>自定义颜色</h5>
    <el-menu
      default-active="2"
      class="el-menu-vertical-demo"
      @open="handleOpen"
      @close="handleClose"
      background-color="#545c64"
      text-color="#fff"
      active-text-color="#ffd04b">
      <el-submenu index="1">
        <template slot="title">
          <i class="el-icon-location"></i>
          <span>导航一</span>
        </template>
        <el-menu-item-group>
          <template slot="title">分组一</template>
          <el-menu-item index="1-1">选项1</el-menu-item>
          <el-menu-item index="1-2">选项2</el-menu-item>
        </el-menu-item-group>
        <el-menu-item-group title="分组2">
          <el-menu-item index="1-3">选项3</el-menu-item>
        </el-menu-item-group>
        <el-submenu index="1-4">
          <template slot="title">选项4</template>
          <el-menu-item index="1-4-1">选项1</el-menu-item>
        </el-submenu>
      </el-submenu>
      <el-menu-item index="2">
        <i class="el-icon-menu"></i>
        <span slot="title">导航二</span>
      </el-menu-item>
      <el-menu-item index="3" disabled>
        <i class="el-icon-document"></i>
        <span slot="title">导航三</span>
      </el-menu-item>
      <el-menu-item index="4">
        <i class="el-icon-setting"></i>
        <span slot="title">导航四</span>
      </el-menu-item>
    </el-menu>
  </el-col>
</el-row>

<script>
  export default {
    methods: {
      handleOpen(key, keyPath) {
        console.log(key, keyPath);
      },
      handleClose(key, keyPath) {
        console.log(key, keyPath);
      }
    }
  }
</script>

3.展开折叠

<el-radio-group v-model="isCollapse" style="margin-bottom: 20px;">
  <el-radio-button :label="false">展开</el-radio-button>
  <el-radio-button :label="true">收起</el-radio-button>
</el-radio-group>
<el-menu default-active="1-4-1" class="el-menu-vertical-demo" @open="handleOpen" @close="handleClose" :collapse="isCollapse">
  <el-submenu index="1">
    <template slot="title">
      <i class="el-icon-location"></i>
      <span slot="title">导航一</span>
    </template>
    <el-menu-item-group>
      <span slot="title">分组一</span>
      <el-menu-item index="1-1">选项1</el-menu-item>
      <el-menu-item index="1-2">选项2</el-menu-item>
    </el-menu-item-group>
    <el-menu-item-group title="分组2">
      <el-menu-item index="1-3">选项3</el-menu-item>
    </el-menu-item-group>
    <el-submenu index="1-4">
      <span slot="title">选项4</span>
      <el-menu-item index="1-4-1">选项1</el-menu-item>
    </el-submenu>
  </el-submenu>
  <el-menu-item index="2">
    <i class="el-icon-menu"></i>
    <span slot="title">导航二</span>
  </el-menu-item>
  <el-menu-item index="3" disabled>
    <i class="el-icon-document"></i>
    <span slot="title">导航三</span>
  </el-menu-item>
  <el-menu-item index="4">
    <i class="el-icon-setting"></i>
    <span slot="title">导航四</span>
  </el-menu-item>
</el-menu>

<style>
  .el-menu-vertical-demo:not(.el-menu--collapse) {
    width: 200px;
    min-height: 400px;
  }
</style>

<script>
  export default {
    data() {
      return {
        isCollapse: true
      };
    },
    methods: {
      handleOpen(key, keyPath) {
        console.log(key, keyPath);
      },
      handleClose(key, keyPath) {
        console.log(key, keyPath);
      }
    }
  }
</script>