cr/src/view/navigationBar.vue

<template>
<section>
        <div id="child_menu">
	        <div class="left">
		        <label>行数</label>
		        <input type="text" style="width: 40px" v-model="sum_copy"/>
		        <label @click="changeSum" style="cursor: pointer">确认</label>
	        </div>
            <div class="right">
                <label>设置</label> &nbsp;&nbsp;&nbsp; <label>删除</label>
            </div>
        </div>
        <child v-bind:sum="this.sum"></child>
</section>
</template>
<script>
import child from '@/components/common/list';

let data = () => {
  return {
    collapsed: false,
	sum:1,
    sum_copy:1,
  }
}

let changeSum = function(){
    this.sum = this.sum_copy * 8
}

export default {
    data: data,
    methods: {
      changeSum
    },
    components:{
      child
    }
}
</script>