bulma menu toggle in gatsbyjs not working

GatsbyJS beginner here, trying to get the Bulma responsive menu toggle to apply the "is-active" class to the menu (gatsby v2 with gatsby starter netlify cms). all code here: https://github.com/pddew/gatsby-starter-netlify-cms

Currently the toggle button and script tags appear but the button doesn't respond.

There is a working version of this in the gatsby starter business- when I inspect and compare my site with this, I can't spot the error, only that there is no event listener on toggle button, when it seems there should be. When I inspect the site, the toggle.js script is being called and put in before the closing body tag, and the viewed.

I have tried building and deploying with no luck, clearing caches and swapping the scripts for bulma's suggested code.

Here is the relevant code. Any help with this greatly appreciated; I'm a bit stuck!

in Layout.js:

    import React from 'react' import Helmet from 'react-helmet'

import Navbar from '../components/Navbar' import Footer from '../components/Footer' import './all.sass'

const TemplateWrapper = ({ children }) => (   <div>
    <Helmet title="Immediate Start Jobs" />
    <Navbar />
    <div>{children}</div>
    <Footer />   </div> )

export default TemplateWrapper

in Navbar:

<button className="button navbar-burger" data-target="navMenu">
      <span />
      <span />
      <span />
    </button>
  </div>
  <div className="navbar-menu" id="navMenu">
    <div className="navbar-start">
      <Link className="navbar-item" to="/about">
        About
      </Link>
      <Link className="navbar-item" to="/products">
        Products
      </Link>
      <Link className="navbar-item" to="/blog">
      Blog
    </Link>
    </div>

in html.js

    import React from "react"
import PropTypes from "prop-types"

export default class HTML extends React.Component {
  render() {
    return (
      <html {...this.props.htmlAttributes}>
        <head>
          <meta charSet="utf-8" />
          <meta httpEquiv="x-ua-compatible" content="ie=edge" />
          <meta
            name="viewport"
            content="width=device-width, initial-scale=1, shrink-to-fit=no"
          />
          {this.props.headComponents}
        </head>
        <body {...this.props.bodyAttributes}>
          {this.props.preBodyComponents}
          <div
            key={`body`}
            id="___gatsby"
            dangerouslySetInnerHTML={{ __html: this.props.body }}
          />
          {this.props.postBodyComponents}
          <script src={__PATH_PREFIX__ + '/js/toggle.js'} />

        </body>
      </html>
    )
  }
}

HTML.propTypes = {
  htmlAttributes: PropTypes.object,
  headComponents: PropTypes.array,
  bodyAttributes: PropTypes.object,
  preBodyComponents: PropTypes.array,
  body: PropTypes.string,
  postBodyComponents: PropTypes.array,
}

And my toggle.js, stored in static/js/

    document.addEventListener('DOMContentLoaded', function () {
  // Get all "navbar-burger" elements
  var $navbarBurgers = Array.prototype.slice.call(document.querySelectorAll('.navbar-burger'), 0)
  // Check if there are any navbar burgers
  if ($navbarBurgers.length > 0) {
    // Add a click event on each of them
    $navbarBurgers.forEach(function ($el) {
      $el.addEventListener('click', function () {
        // Get the target from the "data-target" attribute
        var target = $el.dataset.target
        var $target = document.getElementById(target)
        // Toggle the className on both the "navbar-burger" and the "navbar-menu"
        $el.classList.toggle('is-active')
        $target.classList.toggle('is-active')
      })
    })
  }
})

Solution

I'm new to Gatsby myself, but I had to find a way to get my navbar to function. My solution is pretty quick and dirty, but it works. If your building a website with a lot of components that change state, I would suggest using redux and a central store instead. My solution was just having a navbar that handled its own state.

import React, { Component } from 'react'
import Link from 'gatsby-link'

class Navbar extends Component {

    state = {
        //This sets the state of Bulma elements
        navbarIsActive: "navbar-item has-dropdown"
      }

      //This opens the navbar dropdown
      navbarOpenDropdown = () => {
        this.setState({
          navbarIsActive: "navbar-item has-dropdown is-active"
        })
      }

      //This closes the navbar dropdown
      navbarCloseDropdown = () => {
        this.setState({
          navbarIsActive: "navbar-item has-dropdown"
        })
      }

    render() {
        return(
            <div>
                <nav class="navbar is-transparent" role="navigation" aria-label="dropdown navigation">
                    <a class="navbar-item">
                        <h1>Title!</h1>
                    </a>

                    <div 
                        class={this.state.navbarIsActive}
                        onMouseEnter={this.navbarOpenDropdown}
                        onMouseLeave={this.navbarCloseDropdown}
                        >
                        <a class="navbar-link">
                            Docs
                        </a>

                        <div class="navbar-dropdown is-boxed">
                            <Link to="/">Home</Link>
                            <Link to="/about">About Us</Link>
                            <Link to="/blog">Blog</Link>
                            <hr class="navbar-divider"/>
                            <div class="navbar-item">
                                Version 0.7.2
                            </div>
                        </div>
                    </div>
                </nav>

                <section class="hero">
                    <div class="hero-body">
                        <p class="title">
                            Documentation
                        </p>
                        <p class="subtitle">
                            Everything you need to <strong>create a website</strong> with Bulma
                        </p>
                    </div>
                </section>
            </div>
        )
    }
}

export default Navbar;