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Getting Started

This guide will help you get started using MDC-Web on your own sites and within your own projects.

If you are interested in integrating MDC-Web into a framework, or building a component library for your framework that wraps MDC-Web, check out our framework integration guide.

MDC-Web quick start: building a simple greeting app

The best way to learn any new technology is to get your hands dirty and build something with it, so that is what we will do here! You will be building a simple greeting page which lets you enter a name and greets you as such. Here is the finished example.

As you go through this guide, we encourage you to code along with it. By the end, you will have learned the fundamentals incorporating MDC-Web into simple sites, as well as worked with some of the components we have to offer.

Setting up the project

Create a directory for the project where we'll serve our application out of.

mkdir greeting-app
cd greeting-app

Additionally, if you have NodeJS installed, we recommend installing and using live-server as your local development server. Live-server is simple to use and will reload the page whenever you make a change to your HTML. You can install it via npm by typing the following:

npm install --global live-server

NOTE: You may need to use sudo to install npm packages globally, depending on how your node installation is configured.

The --global flag tells npm to install the package globally, so that the live-server program will be available on your $PATH.

Creating the skeleton index.html file

Now that you have a directory set up, create a simple index.html file, and include the assets needed for MDC-Web. Put the following within index.html in the greeting-app directory:

<!DOCTYPE html>
<html class="mdc-typography">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1">
    <title>Greeting App</title>
    <link
      rel="stylesheet"
      href="https://unpkg.com/material-components-web@latest/dist/material-components-web.min.css">
  </head>
  <body>
    <h1 class="mdc-typography--display1">Hello, World!</h1>
    <button type="button" class="mdc-button mdc-button--raised mdc-button--primary">
      Press Me
    </button>
  </body>
</html>

View this page by running live-server (or the web server of your choice) within the greeting-app directory.

If you're using live-server, this will open up your browser to the URL which is serving our index.html file. You can leave live-server running for the duration of this guide. If you're not using live-server, navigate to the web server's base URL and view the page. Also be sure to refresh after every change you make!

Let's take a look at a few aspects of the above HTML.

  • No JavaScript necessary (yet) - Because we aren't using any dynamic components, we only need to include the MDC-Web CSS, so that we can apply the proper CSS classes to our elements. With MDC-Web, JavaScript is only necessary for dynamic components whose UI needs to be made aware of events happening on the page. As we develop our greeting app, we'll add in the necessary JavaScript.
  • No automatic DOM rendering - For all components, MDC-Web does not render any DOM elements itself. MDC-Web is similar to Bootstrap in this respect; it expects you to render the DOM using the proper CSS classes. This avoids a litany of problems for integrating MDC-Web into complex applications.
  • Elements are not natively styled - Notice how above, we give the <html> element a class of mdc-typography, the <h1> element a class of mdc-typography--display1, and the button a class of mdc-button, along with multiple modifier classes. MDC-Web never makes any assumptions about which elements are being used for our components, instead relying on CSS classes for maximum flexibility. MDC-Web's CSS class names follow a slightly modified version of the BEM system.

Adding in JavaScript for dynamic components

Now that we've gotten the gist of MDC-Web, let us continue to build our greeting app.

The app consists of two input fields and a submit button. Material Design text input fields and buttons contain a lot of dynamism and animation that require the usage of JavaScript.

Replace the contents of the <body> tag in index.html with the following:

<main>
  <h1 class="mdc-typography--display1">Tell us about yourself!</h1>

  <form action="#" id="greeting-form">
    <div>
      <div class="mdc-form-field">
        <div class="mdc-textfield" data-mdc-auto-init="MDCTextfield">
          <input id="firstname" type="text" class="mdc-textfield__input">
          <label for="firstname" class="mdc-textfield__label">
            First Name
          </label>
        </div>
      </div>

      <div class="mdc-form-field">
        <div class="mdc-textfield" data-mdc-auto-init="MDCTextfield">
          <input id="lastname" type="text" class="mdc-textfield__input">
          <label for="lastname" class="mdc-textfield__label">
            Last Name
          </label>
        </div>
      </div>
    </div>

    <button type="submit"
            class="mdc-button
                   mdc-button--raised
                   mdc-button--primary
                   mdc-ripple-surface"
            data-mdc-auto-init="MDCRipple">
      Print Greeting
    </button>
  </form>

  <!-- The p element below is where we'll eventually output our greeting -->
  <p class="mdc-typography--headline" id="greeting"></p>
</main>

<script src="https://unpkg.com/material-components-web@latest/dist/material-components-web.min.js"></script>
<script>window.mdc.autoInit();</script>

Once the changes are made, return to your browser and you will see two very nicely styled form fields along with a Material Design styled button. The button shows an ink ripple effect when pressed. For now, the ripple is a fairly subtle that will be addressed shortly.

Two important points that are demonstrated in the code that was added:

MDC-Web does not instantiate any components automatically

This avoids the headaches involved with lifecycle handlers management in Material Design Lite (the predecessor to MDC-Web). Initialization is done through the data-mdc-auto-init attributes added to those elements that are initialized when mdc.autoInit() is called.

When mdc.autoInit() is called, it looks for all elements with a data-mdc-auto-init attribute, and attaches the MDC-Web JS Component with the given class name to that element.. So when it sees MDCTextfield, it instantiates a MDCTextfield instance to the corresponding elements. It does the same thing for the button, attaching a MDCRipple instance to the element.

It is worth noting that mdc.autoInit is provided purely as a convenience function, and is not required to actually use the components. It is, however, the simplest way to get up and running quickly, and recommended for static sites that use the comprehensive material-components-web library.

All components are modular

Although when you initially set up this project you installed the material-components-web package, that package is simply a thin wrapper around individual component packages, such as mdc-typography, mdc-button, mdc-textfield, and mdc-ripple. Even the autoInit() function lives in its own package, which the material-components-web package uses to register all of the individual components to their names used within data-mdc-auto-init. Each component can be used as a standalone package, and can be mixed and matched at will. This allows for custom builds requiring the minimum possible amount of CSS/JS code. It also means that MDC-Web works extremely well with module loading systems and modern front-end toolchains.

Adding the business logic

Finally, let's add our (very simple) business logic to the bottom of the page, which intercepts the form submission and uses the input field values to print out an appropriate greeting. Add the following below the last <script> tag within the <body>:

<script>
  document.getElementById('greeting-form').addEventListener('submit', function(evt) {
    evt.preventDefault();
    var firstname = evt.target.elements.firstname.value;
    var lastname = evt.target.elements.lastname.value;
    var greeting = 'Hello';
    if (firstname || lastname) {
      greeting += ', ';
      if (firstname && lastname) {
        greeting += firstname + ' ' + lastname;
      } else if (lastname) {
        greeting += 'Mx. ' + lastname;
      } else {
        greeting += firstname;
      }
    }
    greeting += '!';

    document.getElementById('greeting').textContent = greeting;
  });
</script>

When you save the file and the page reloads, you should be able to type your name into the form, hit the button, and get a pleasant greeting 👋

Changing the theme

You may have noticed that the button background, as well as the label and underline on focused text input fields, defaults to the Indigo 500 (#673AB7) color from the Material Design color palette. This is part of the default theme that ships with MDC-Web; it uses Indigo 500 for a primary color, and Pink A200 (#FF4081) for an accent color. Let's change the theme's primary color.

A common misconception when implementing Material Design is that the colors you use must come from the Material Design color palette. This is not true at all. The only defining guideline for color within Material Design is that it has "bold hues juxtaposed with muted environments, deep shadows, and bright highlights". Let's change our theme's primary color to #0E4EAD, the "Afternoon_Skyblue" color from the Deep_Skyblues Colourlovers Palette.

The easiest way to change the theme of an MDC-Web application is via CSS Variables. Simply add the following to the <head> tag of index.html:

<style>
  :root {
    --mdc-theme-primary: #0e4ead;
  }
</style>

If you are using any modern browser besides Edge (which is currently working on it), you'll see that the button background as well as the focused underline and label on text fields are now a nice, dark shade of blue.

Note that using CSS Variables is just one way of theming using MDC-Web. Check out our theming documentation for more info.

Finishing touches: adding custom styles

Every site is different, and we cannot hope to build a user interface library that anticipates every design choice a user may want. MDC-Web uses plain old CSS to make it trivial to customize and modify its styles to your liking. Let's change the ripple color to be a more opaque shade of white, as well as add some auxiliary styles to bump up the vertical spacing between the form fields and the submit button.

Add the following to the <style> tag within <head>:

.mdc-ripple-surface.mdc-ripple-upgraded.mdc-button--primary::before,
.mdc-ripple-surface.mdc-ripple-upgraded.mdc-button--primary::after {
  background-color: rgba(255, 255, 255, .2);
}

#greeting-form > button {
  margin-top: 8px;
}

Congrats! You've built your first MDC-Web app! In the process, you've learned the basics of MDC-Web, how to easily add components to a page, and how to customize and theme MDC-Web to your liking.

Next steps

If you're looking to incorporate MDC-Web Components into a framework like Angular or React, check our framework integration guide. You can also take a look at our framework examples directory which contains examples integrating MDC-Web components into popular front-end frameworks. It also shows how you can use our source ES2015 and SCSS files directly within your own code, for maximum flexibility, modularity, and code size reduction.

If you'd like to contribute to MDC-Web and build your own components, or extend one of ours to fit your own purposes, check out our guide on authoring components.