Lifecycle and Template Refs in Vue 3: A Comprehensive Guide

In Vue 3, the lifecycle of a component refers to the different stages a component goes through from its creation to its destruction. During this lifecycle, a component can perform various tasks, such as fetching data, rendering templates, and reacting to changes in the data or user input. In this tutorial, we'll take a look at the lifecycle of a Vue 3 component, and how to use template refs to access DOM elements in templates.

One of the key features of Vue 3 is its reactive system, which allows components to automatically update when the data they depend on changes. This is achieved through a life cycle of reactive updates, which starts when a component is created and ends when it is destroyed.

The lifecycle of a Vue 3 component can be divided into several stages:

• Creation: The component is created and the data it depends on is initialized.
• Mounting: The component is rendered to the DOM for the first time.
• Updating: The component is updated when the data it depends on changes.
• Destruction: The component is destroyed and removed from the DOM.

During each stage of the life cycle, a component can perform various tasks using lifecycle hooks. Lifecycle hooks are methods that are called at specific points in the lifecycle of a component, and allow you to perform tasks such as fetching data, rendering templates, and reacting to changes in the data or user input.

For example, the beforeCreate hook is called before the component is created, and the created hook is called after the component is created. The beforeMount hook is called before the component is rendered to the DOM, and the mounted hook is called after the component is rendered.

In addition to lifecycle hooks, Vue 3 also provides template refs, which allow you to access DOM elements in templates. To use template refs, you can use the ref attribute to bind a DOM element to a component data property.

For example, let's say you have a template with an input element, and you want to access the value of the input element in the component:

<template>
  <input ref="input" v-model="value">
</template>

<script>
export default {
  data() {
    return {
      value: '',
    };
  },
  mounted() {
    console.log(this.$refs.input.value); // logs the value of the input element
  },
};
</script>

In this example, the ref attribute is used to bind the input element to the input ref, and the mounted hook is used to access the value of the input element in the component.

By using lifecycle hooks and template refs, you can build powerful and reactive UIs with Vue 3. Whether you're building a simple form or a complex single-page application, understanding the lifecycle of a component and how to access DOM elements in templates is a key part of building dynamic and interactive UIs with Vue 3.