vue理解$nextTick

首先要明确：

1. Vue 实现响应式并不是数据发生变化之后 DOM 立即变化，而是按一定的策略进行 DOM 的更新。

2. $nextTick 是在下次 DOM 更新循环结束之后执行延迟回调，在修改数据之后使用 $nextTick，则可以在回调中获取更新后的 DOM

实例

  
{{msg}}
  
Message got outside $nextTick: {{msg1}}
  
Message got inside $nextTick: {{msg2}}
  
Message got outside $nextTick: {{msg3}}
  
    Change the Message
  


new Vue({
  el: '.app',
  data: {
    msg: 'Hello Vue.',
    msg1: '',
    msg2: '',
    msg3: ''
  },
  methods: {
    changeMsg() {
      this.msg = "Hello world."
      this.msg1 = this.$refs.msgDiv.innerHTML
      this.$nextTick(() => {
        this.msg2 = this.$refs.msgDiv.innerHTML
      })
      this.msg3 = this.$refs.msgDiv.innerHTML
    }
  }
})


//结果
Message got outside $nextTick:Hello Vue.
Message got inside $nextTick:Hello world.
Message got outside $nextTick: Hello Vue.

参考

理解 $nextTick 的作用

转载于:https://www.cnblogs.com/redirect/p/8436019.html