How to include jquery in vue component?

Question

JavaScript

My component

<template>
  <div>Шапка</div>
</template>
<script>
import cookies from 'js-cookie'
export default {
  name: 'navigation',
  props: ['backend'],
  data() {
    return {
      isLogin: !!cookies.get('user')
    }
  },
  methods: {
    login() {
      this.$store.commit('global/showLoginModal', true)
    },
    search(e) {
      var qs = e.target.value
      if (qs === '') {
        return false
      }
      this.$router.replace('/search/' + qs)
    }
  }
}
</script>

Need to add to it

var searchBar = $(".search"),
  searchInput = searchBar.find("input"),
  searchToggleBtn = $(".search-toggle"),
  searchParent = $("header_content");
searchInput.on("focus", function() {
  searchBar.addClass("expanded")
}), searchInput.on("blur", function() {
  $(this).val() || searchBar.removeClass("expanded")
}), searchToggleBtn.on("click", function() {
  $(this).toggleClass("active"), searchParent.toggleClass("search"), searchBar.toggleClass("visible"), searchInput.focus()
});

Answer 1

Pull it up with a lifecycle hook mounted().
Article about it

Answer 2

You don't need jQuery to pull so much unnecessary code.
Seems like it should work

let searchBar       = document.querySelector('.search'),
    searchInput     = searchBar.querySelector('input'),
    searchToggleBtn = document.querySelector('.search-toggle'),
    searchParent    = document.querySelector('.header_content');

searchInput.addEventListener('focus', function (event) {
    searchBar.classList.add('expanded');
});
searchInput.addEventListener('blur', function (event) {
    searchInput.value || searchBar.classList.remove('expanded');
});
searchToggleBtn.addEventListener('click', function (event) {
    searchToggleBtn.classList.toggle('active');
    searchParent.classList.toggle('search');
    searchBar.classList.toggle('visible');
    searchInput.focus();
});

Answer 3

As an option, like this:

import JQuery from 'jquery'
let $ = JQuery

In general, this is quite redundant, to drag jquery as well. I advise you to rewrite the code on ecma, it will even be the same size, and it will all work much faster.