使用 vue v-if 后什么时候元素在 dom 中可用

When does an element become available in dom after using vue v-if

使用 vue v-if 后,什么时候元素在 dom 中可用?我原以为您可以在 v-if 计算结果为真后对元素执行查询选择器?

在下面的代码中,我需要在显示弹出窗口后获取 .test 元素,但它显示为 null - 如何获取它?

new Vue({
  el: "#app",
  data() {
    return {
      showPopout: false,
    };
  },
  methods: {
    buttonClick(day) {
      this.showPopout = true;
      console.log(document.querySelector('.test'));
    },
  },
});
<script src="https://unpkg.com/vue@2.6.14/dist/vue.js"></script>
<div id='app'>
  <span @click="buttonClick">show popout</span>
  <div v-if="showPopout"><span class="test">test</span></div>
</div>

nextTick

后会有

new Vue({
  el: "#app",
  data() {
    return {
      showPopout: false,
    };
  },
  methods: {
    buttonClick(day) {
      this.showPopout = true;
      this.$nextTick(() => {
        console.log(document.querySelector('.test'));
      });
    },
  },
});
<script src="https://unpkg.com/vue@2.6.14/dist/vue.js"></script>
<div id='app'>
  <span @click="buttonClick">show popout</span>
  <div v-if="showPopout"><span class="test">test</span></div>
</div>