can I use ref on vue component code example

Example 1: vuejs ref

<template>
	<input ref="input">
</template>

<script>
  export default {
    methods: {
	  // used to put the focus on this field from the parent
      focus() {
        this.$refs.input.focus();
      }
    }
  };
</script>

Example 2: passing $refs inner component vue

<user>
  <user-item ref="details"></user-item>
  <permissions :parentRefs="$refs"></permissions>
</user>