A Mercedes-Benz R&D North America, Seattle HUB contribution

Use web components with React properties and functions

import React from "react"; import reactifyWc from "reactify-wc"; // Import your web component. This one defines a tag called 'vaadin-button' import "@vaadin/vaadin-button"; const onClick = () => console.log("hello world"); const VaadinButton = reactifyWc("vaadin-button"); export const MyReactComponent = () => ( <> <h1>Hello world</h1> <VaadinButton onClick={onClick}>Click me!</VaadinButton> </> );

React does not handle properties and functions correctly for web components. This factory function returns a new React component for a given web component so you can use them.

Children are dropped directly into the web component like normal.

reactify-wc checks the passed properties by type to determine where they should go. strings, numbers, and booleans are set as attributes on the web component. All other data besides functions that have a property name that begin with /^on[A-Z]/ and children are set as props.

Any function that has a property name that starts with on[A-Z] (any string that starts with 'o', 'n', and any uppercase letter) is truncated and the first char toLowerCased before passing to addEventListener. This effectively means onClick becomes a handler for the click event. This is to make things easy when handling most React synthetic events which typically have direct DOM companions by name. You can target kebab-cased custom events in the same way, like onMy-kebab-event -> my-kebab-event. function properties that do not start with on[A-Z] are added as props. Observe the example below:

const Example = () => ( <VaadinButton onClick={handleClick}>Click</VaadinButton> // calls addEventListener('click', handleClick) // The 'on' prefix is truncated, and the next char lowercased <VaadinButton functionalProp={functionalProp}>Click</VaadinButton>  // adds a prop 'functionalProp' -> functionalProp )

Events passed into the event handlers are browser events, not React SyntheticEvents.

Many web components are "composable," meaning that in order to get a desired functionality, you may need to put multiple tags together or inside one another. Technically speaking, when using reactify-wc, only top level web components and components that have direct React integration need to be reactified. For readability and ease of use, we recommend reactifying all web components if possible.

// Preferred method const VaadinGrid = reactifyWc("vaadin-grid"); const VaadinGridColumn = reactifyWc("vaadin-grid-column"); const MyReactComponent = () => ( <VaadinGrid items={items}> <VaadinGridColumn path="name.first" header="First name" onClick={onClick} /> <VaadinGridColumn path="name.last" header="Last name" /> </VaadinGrid> );

// Will work, not preferred const VaadinGrid = reactifyWc("vaadin-grid"); const MyReactComponent = () => ( <VaadinGrid items={items}> <vaadin-grid-column path="name.first" header="First name" /> <vaadin-grid-column path="name.last" header="Last name" /> </vaadin-grid> );

// Will work, not preferred const VaadinGrid = reactifyWc("vaadin-grid"); const VaadinGridColumn = reactifyWc("vaadin-grid-column"); const MyReactComponent = () => ( <VaadinGrid items={items}> <VaadinGridColumn path="name.first" header="First Name" onClick={onClick} /> <vaadin-grid-column path="name.last" header="Last Name" /> </VaadinGrid> );

You can mix and match your reactified web components and React components:

const WriteNames = ({ names }) => names.map(name => <p>{name}</p>); const ReactifiedWc = reactifyWc("web-comp"); const names = ["Bryce", "Brion", "Pia", "Fabian"]; const MyComponent = () => ( <ReactifiedWc> <WriteNames names={names} /> </ReactifiedWc> );

Contribute to the project in our git repo by opening a PR with changes. We have no official contribution guide yet.

• Do some deep comparison between the changing props, attributes, and especially event handlers so that we aren't setting and removing them on every componentDidUpdate.

This software was created in-house at Mercedes-Benz Research & Development North America, Seattle HUB. This software is provided under the MIT license. We're hiring!