Rendering Menu

In components/MenuPage.js add the following methods

connectedCallback() {
    window.addEventListener("appmenuchange", () => {
        this.render();
    });
    this.render();
}

render() {
    if (app.store.menu) {
        this.root.querySelector("#menu").innerHTML = "";
        for (let category of app.store.menu) {
            const liCategory = document.createElement("li");
            liCategory.innerHTML = `
                <h3>${category.name}</h3>
                <ul class='category'>
                </ul>`;
            this.root.querySelector("#menu").appendChild(liCategory);

            // TODO: placeholder
        }  
    } else {
        this.root.querySelector("#menu").innerHTML = `Loading...`;
    }
}