develop an app for windows 8 using html5

AGENDA

of my page.

I’m a Web developer, I don’t know (at all) Microsoft technologies.

I already developed an HTML5 web page.

I want to create the

Windows 8app

My existing web page: home.dollon.net

Compatible with all last browsers on PC and tablets.Works with HTML5 and CSS3 features, knockout.js, jQuery, less (and node.js web service)

DEMO

So now, please Microsoft, where is the right button click

“Transform this website as a metro style app for Windows8”?

It does not exist. And it’s normal.

Because you are working for a specific kind of tablet with native call (new API, new controls…) and NEW design style (metro).

You are not designing a web page. You are developing a

native app.

9 things to migrate your HTML5 app on

Windows 8 environment.

0 – which kind of tools I need?**this point is not included on the counter ☺

DEMO

1 - what is a package?

a package is a ZIP file

It’s the ‘executable’ of your project

It contains everything (HTML, JS, Manifest..)

Don’t forget to obfuscate your code

After installation, the app is located here c:\Program Files\WindowsApps

You can use PowerShellto deploy it

And all packages are signed with certificates

2 – what happens in runtime?

The process that hosts/executes a Metro style app using JavaScript is called WWAHost.exe

Your app ‘live’ inside a sandbox without all privileges of the current user

Process state transitions

A user

launch an

app

App is

runningSuspended Terminated

An app gets 5 secondes to handle suspend and is notified when it has been resumedApp is not notified before a termination caused by low resources

3 – Differences between Metro style app

And traditional HTML5 web page

ALL*HTML5/CSS3 features are supported

*if IE10 “trident” layout engine support it

ALL*JavaScript features are supported

*if IE10 “Chakra” engine support it

DOM EventsNative APIs

NamespacesControls Enumerations

Some ActiveX controls are disabled

No Java, Silverlight, Flash and other embedded components

have the same support of web APIsthan IE 10

So, HTML5, CSS3 and JavaScript

+

API from WinRT

seriously

And you have to know that

ROCKS!

This isn’t just a container like PhoneGap

It doesn’t run in a browser

REUSE THE SAME CODEJust to see if it works ☺

4 – what is WinRT?

Windows RT != WinRT(Windows RT is the Windows 8 version for ARM)

WinRTResides directly on the top of the kernel

just like the Win32 API

WinRT APIs are written in unmanaged C++ and designed to be object-oriented

5 – what is WinJS?

WinJS is the orange layer

A language projection exists for .NET and C++ too

Windows library for JSHelpers

AnimationsTemplates Styles

Navigation

Data Binding

Controls

App Model

Base.js

Wwaap.jsUi.js

Binding.js

Controls.jsAnimation.js

6 – Windows Controls

Built-in ControlsMetro-UI Styles

Touch enabledNative Customizable

Same in XAMLControls

All basic controls

AppBarUseful to bring up commands on demand

Don’t forget to use Charms for some entry points

MODIFY THE APPWith Windows 8 controls

7 – Multiple Views andResolutions

The principal screen can be at minimum 1024x768

It exists widescreen (1366x768+)

Two other modes: snapview and portait

Use three kind of image size (100%, 140% and 180%).

Depending on the resolutions, images are loaded automatically

Image.jpg � Image.scale-180.jpg

Use of CSS media queries

MODIFY THE APPScreens

7 – Use Contracts

Share to export the current content

Search to find content

File Picker to allow user to access content from outside

Settings to configure the app

MODIFY THE APPContracts

8 – Use Tiles

Tiles is the “link” to open your appIt could be a “secondary tiles”Can provide a lot of information (icons, notifications, counter)

MODIFY THE APPWith Tiles and Splash

9 – Debugging and Performances

PerformanceTips & tricks that still work:For safe dynamic content, use innerHTMLLink CSS stylesheets at the top of the pageAvoid inline JavaScript and inline CSS stylesDon’t parse JSON by hand, use JSON.parse

A Metro style app using HTML5is more than a web page …

Rely on packaged content and local dataUse local images scaled to the right sizeUse WinJS fragments to load parts of your app on demand

Defer parsing of unneeded HTML contentDelays JavaScriptKeeps your DOM small: look-up and manipulations are quicker

Optimize your landing page

Defer some initialization to after the splash screenStart network downloads after initializationDelay loading databases

Consolidate small JS files that are related into larger filesIf you need more time, use an extended splash screen

Further optimizations

Keep a lightweight DOMRelease expensive content, such as media elements, as soon as they are no longer neededHelp the garbage collector

Avoid circular references between your elements and JavaScript codeReview how you use your Object URLs

Manage your resources

On suspend, free resources that are easy to recreateUse media content from the user at the screen resolutionTune your app launch time to create great first impressionsKeep your app alive by minimizing your memory footprintBe responsive, don’t block the UI thread

Debugging JavaScript apps is !@#$%^ hard!

Debugging with Visual Studio

Launch with debuggingdebugger keywordDebug.enableFirstChanceException(true);JavaScript consoleDOM explorer

Debugging with BlendUnderstand your CSS with the Winning Rule and Show Set Properties modeDebug device-state issues with the Platform and Styles PanesCatch grid layout issuesFind parser-generated elements with the Live DOMDiagnose post-interaction problems with Interactive Mode

10 – DeploymentBut no info now, it still not possible to publish app

Result

ConclusionSkydrive with all samples / slides / videos:

Webcast of this session on YouTube:

http://sdrv.ms/KsoFUq

Q&A(Don’t hesitate to give us feedbacks on twitter @juliendollon/ @soumow)