How made a scroll modal on Vue?

Im trying to find a way to display a modal on Vuejs, when i scrolling down ( > 450 px) a page, the problem is i got nothing on my screen when i compile the code .

<template>
  <h2 id="modal">Modal Example</h2> 
  <div id="app">
  	<Modal v-if="showModal" @closeModal="showModal = false" />
  </div> 
   <p>



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  </p>

</template>
 
<script>
import Modal from './Modal.vue';
export default {
  components: {
    Modal,
  },
  data: () => ({
    showModal: false,
    scrollHeight: 0,
    interval: null,
  }),
  methods: {
    handleScroll() {
      this.handleDebouncedScroll = window.scrollY > 0;
    },
  },
  mounted() {
    this.interval = setInterval(() => {
      this.scrollHeight = document.body.scrollHeight;
    }, 100);
  },
  unmounted() {
    clearInterval(this.interval);
  },
  watch: {
    scrollHeight() {
      if (this.scrollHeight === 450) this.showModal = true;
    },
  },
};
</script>

Without really checking the rest of the code: I think you problem is here:

Initially scrollHeight is 0. Then the user scrolls down and you periodically update scrollHeight. Eventually the user scrolls down past the 450 mark β€” let’s say to 453 β€” and your check fails again as 453 !== 450. Try with if (this.scrollHeight >= 450) (and maybe add an else branch to set showModal back to false if the user scrolls up).

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