给标题字段前添加红星，使这个标题是必填。

Question

设置”设备信息“为必填项，在它前边出现红色星。

 <el-row :gutter="20">
        <el-tabs v-model="activeName" @tab-click="handleClick">
          <el-tab-pane label="施肥计划" name="manure"><manure ref="manure" :jobId="jobId" :section="selectSection"></manure></el-tab-pane>
          <el-tab-pane label="苗木计划" name="sapling"><sapling ref="sapling" :jobId="jobId" :section="selectSection"></sapling></el-tab-pane>
          <el-tab-pane label="浇水计划" name="water"><water ref="water" :jobId="jobId" :section="selectSection"></water></el-tab-pane>
          <el-tab-pane label="人员信息" name="person"><person ref="person" :selectRow="this.selectRow" :jobId="jobId"></person></el-tab-pane>
          <el-tab-pane label="设备信息" name="device"><device ref="device" :selectRow="this.selectRow" :jobId="jobId"></device></el-tab-pane>
        </el-tabs>

Answer 1

<el-tab-pane label="施肥计划" name="manure"><span slot="label"><i style="color:#f00">*</i>施肥计划</span><manure ref="manure" :jobId="jobId" :section="selectSection"></manure></el-tab-pane>