Fundamentals of Mobile Web Development

At Chrome Dev Summit 2014 there was a whole host of topics and brand spanking new API's covered, but its not all about the new and shiny.

If you are a new Web Developer or even an experienced developer about to embark on exploring new APIs, chances are you'll follow these three steps: learn, build and iterate.

Matt Gaunt covers the ongoing efforts to address these problems from the Chrome Developer Platform team.

Learn.

Web Fundamentals on a HTML5Rocks

Web Fundamentals is a set of use case led documentation covering a range of topics. The core goal is get developers from little or no knowledge, to implementing best practices as quickly as possible.

One of the main goals of Web Fundamentals is to ensure that if you are new to a topic, the guidance reduces "choice paralysis" as much as possible. Addy Osmani covers this perfectly over at Pastry Box.

If you do spot any issues with the site or it's content or you'd like Web Fundamentals to cover a particular topic, then please do let us know by submitting feedback on Github.

Build.

Web Starter Kit on a Range Devices

To help you kick off a new web project we created Web Starter Kit. It has everything you need:

  • A solid build process
  • Boilerplate HTML
  • Styleguide

The Build Process

For those of you who are new to build processes, the easiest way to think of a build process is to view it as a program which takes a set of files and performs certain tasks on them and outputs new versions in a different location. The tasks optimise the files to improve load times, check for possible errors or handle tasks that can be automated.

In Web Starter Kit we have the following processes:

Diagram of Web Starter Kits Build Process

We minify and concatenate CSS and Javascript so that the browser can fetch the file quickly, the Javascript is also run through JSHint to check for Javascript best practices and common coding mistakes. Images are minified with imagemin and you can get huge reductions in file size by using this. We also have a process to create the styleguides CSS.

Boilerplate for Multi-Device HTML

The first set of HTML you write for a new page is pretty bog standard and chances are you'll have some way of quickly getting hold a stock HTML file that works well across multiple devices and screen sizes.

In Web Starter Kit we wanted to add in support for any features which blurred the lines between the platform and your site, so we've added support for add to home screen and splash screens for Android, Windows Phone, iOS and Opera Coast.

Example of Web Starter Kit Add to home screen

Styleguide

Web Starter Kit Styleguide on Chromebook Pixel

The final piece of Web Starter Kit is it's Styleguide.

This gives any new project a great set of default styles and components that encourages style driven development. You can alter existing styles to elements and add your own.

In the next version of WSK, due for release early next year, we are working hard to simplify how the styleguide fits together and switching to a Material Design look and feel. Matt showed an early mock of what this may look like at Chrome Dev Summit and you can see an example below.

Web Starter Kit's Material Design Styleguide Mock

Iterate.

Once you've started to put your new knowledge into practice, you'll want to use DevTools to debug, improve and maintain your work.

There are some huge new features landing in DevTools and Matt takes a look at the following new features.

Device Mode

Device mode is a new section in DevTools which allows you to quickly see how your site works across different mobile devices, while viewing the media queries in your CSS.

Screenshot of Device Mode Feature in Chrome DevTools

One of the great features of Device Mode is the ability to throttle the network speeds, allowing you simulate the experience of a user on a GPRS, EDGE, 3G, DSL or Wifi connection.

Screenshot of Network Throttling in Chrome DevTools

Paint Profiler

If you've ever opened up the timeline tab and hit the record button, you've probably seen some paint events happen in the waterfall. Normally this would be a black box with no way for you to know why the browser had done, or what it was doing.

Paint profiler no gives you more information on what exactly the browser is doing during that paint.

Screenshot of the Paint Profiler in Chrome DevTools

Invalidation Tracking

DevTools now gives a reason why a paint or layout occurred whenever it can, this is useful for anyone learning about the timeline, the browser behaviours and allows you to optimise your code to prevent performance issues.

Screenshot of Invalidation Tracking in Chrome Devtools

Flame Chart View

This is a very different way of viewing the information available in the timeline. This makes it much easier to see how tasks overlap and what browser behaviour happened as a result of other tasks.

Screenshot of Flame Chart View in Chrome DevTools

Frame Viewer

While in Flame Chart view, you can select a specific frame and within this, you'll be able to explore which elements in the page had been promoted to a composite layer as well as why they've been promoted.

Screenshot of Frame Viewer in Chrome DevTools

Learn. Build. Iterate.

These are some of the efforts from the Chrome team to help developers get up to speed with web development, so be sure to check out Web Fundamentals, Web Starter Kit and the new features in Chrome DevTools.