Karl Wilcox

Tutorial Starts at 19:00

TT284: Web Technologies

Block 3: Mobile Content and Applications

TT284-12B Block 3 Tutorial

Tutorial begins at 7pm and will be recorded.Please run the audio setup.

IMPORTANT!Be sure to check the News section on the TT284 Website regularly....

....and check the TMA 03 Forum for clarifications and updates BEFORE you submit your TMA!

3

Hello And Welcome

• Welcome

• Start recording….

HTTP://XKCD.COM/479/

Agenda

• Review – Where are we & how did we get here?• Feedback on TMA02• Mobile Devices – Some thoughts• Mobile devices, handling and detection• XSLT Transforms

– (A note on XML name spaces)

• Apps for mobile• TMA03 – Questions and queries?• Reminders

I have material for about 1 hour……can use additional time for Q&A if required

Practicals

Where are we?

What Have We Learnt?

• XHMTL – Content description language for web pages• CSS – Styling information for web pages (and other

things)• Page Design – Guidelines for layout (user expectations)• Site Navigation – Consistency, ease of use• Accessibility – Guidelines, testability• PHP – Server side language for content management• Javascript – client side language for interaction

TMA02 Feedback

• Generally good – thank you and well done!

• Long extensions (> 1 week) didn’t really help

• As always – read the question, answer the question– If in doubt, ask me! – I can’t comment on your answers but I can say whether you appear

to have understood the question

• Regular expression misunderstanding, esp. ranges– [1-9] is a range of characters not numbers– [1-99999] does NOT work as some seemed to expect

TMA02 Feedback - 2

• Don’t create unnecessary dependencies– Aim for maximum “abstraction” (independence)

• Examples– Don’t rely on field width to restrict input length

– Don’t rely on database organisation for formatting• Database tables can have new columns added

• Order of elements in an array may change

– Use associative arrays for query results

<td><?php echo $results[‘laptime’]; ?></td>

Health Warning!

• The following presentation contains personal opinion and some scepticism

• It may not be suitable for those who like nice simple answers (and courses!) You will need to be able to make up your own mind…

• “I did not answer this questions as my tutor didn’t think it was worth it” Is NOT acceptable for the next TMA…

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Mobile Devices

• Characteristics• Describe them here please….!

Mobile Device Assumptions• Awkward touch-screen

input• Limited processor

power• Small keyboard• Limited capabilities• Some Web site

navigation and usability features won’t work. For example, drop-down menus

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WAP & WMLA Warning from History• 1999 – mobiles taking off in a big way• Demand (& hype) for mobile internet• But screens only display text…so

• Define new markup language – WML• Design new infrastructure• Publish new comms protocol – WAP• 2003/04 WAP traffic doubles!

– (but from what to what?)

• 2013 WAP / WML use - zero12

The Lesson of WAP

• WAP & WML did not address what people wanted• It addressed what the “lowest common denominator” of

technology could do• It ignored everything that already existed (HTML, HTTP)• It required new technologies and hardware• It was designed to generate revenue for the telecoms

operators

• It did NOT succeed!

• Do not underestimate the ability of technology to provide what people actually want.

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The Lesson of Mobile Broadcast TV

• It is equally hard to push technologies for which there is NO demand

• Mobile broadcast TV is perfectly feasible over 3G networks, handsets had support built in– BUT it turns out that nobody wants to watch broadcast TV on their

phones (except in South Korea…)

• Will this lesson ever be learned…?– Video calling on mobiles (“3”’s big selling point on launch)– 3D-TV ???

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7 usability guidelines for Web sites on mobile devices

1.Reduce the amount of content

2.Single column layouts work best

3.Present the navigation differently

4.Minimise text entry

5.Decide whether you need more than 1 mobile site

6.Design for touchscreen and non-touchscreen users

7.Take advantage of inbuilt functionality

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http://www.webcredible.co.uk/user-friendly-resources/web-usability/mobile-guidelines.shtml (accessed 21/06/12)

Slide used

Last Year

7 usability guidelines for Web sites on (small?) mobile devices1.Reduce the amount of content

Why? Screens are near desktop resolution…

2.Single column layouts work bestAre deeply annoying

3.Present the navigation differentlyAs this will confuse and annoy your users!

4.Minimise text entry Predictive text faster than typing for most…

5.Decide whether you need more than 1 mobile siteBecause we all need MORE work to do!

6.Design for touchscreen and non-touchscreen users

7.Take advantage of inbuilt functionalityLike I wasn’t doing this already…?

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What I think now…

Options for Mobile• Do nothing

• Design one Web site but use a different style sheet or sheets for mobile devices

• Have separate Web sites for mobile devices.

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Check-out the BBC Web site on several devices.

Ripple

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Detecting Mobile Devices (client)

• Infer from “window” object height & width• Use “navigator” object

<!DOCTYPE html><html><body><div id="example"></div><script type="text/javascript">txt = "<p>Browser CodeName: " + navigator.appCodeName + "</p>";txt+= "<p>Browser Name: " + navigator.appName + "</p>";txt+= "<p>Browser Version: " + navigator.appVersion + "</p>";txt+= "<p>Cookies Enabled: " + navigator.cookieEnabled + "</p>";txt+= "<p>Platform: " + navigator.platform + "</p>";txt+= "<p>User-agent header: " + navigator.userAgent + "</p>";document.getElementById("example").innerHTML=txt;</script></body></html>

Browser CodeName: MozillaBrowser Name: NetscapeBrowser Version: 5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.56 Safari/536.5Cookies Enabled: truePlatform: Win32User-agent header: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.56 Safari/536.5

Detecting Mobile Devices (server)

• Browser id strings – www.zytrax.com/tech/web/browser_ids.html

See also detector.dmolsen.com – tries to categorise broswer (desktop, advanced mobile, basic mobile) from browser string

Handling Mobile Devices

• Now we (think) we know the device, how can we deliver appropriate content?

– Switching stylesheets– Tweaking classes and ids– Transforming content– Separate sites– Frameworks (e.g. Wordpress Themes)

More on Transformations

• XSLT capabilities – Good for:– Re-ordering content– Selecting elements– Modifying attributes

• XSLT shortcomings - Not so good at:– Counting stuff (get first ‘n’ items from list)– Being easy to write from scratch– Good starting points at

wwbota.free.fr/XSLT_models/README.html

XML Name Spaces - 1

• May have come across these reading about XSLT• One approach to problem of mixing different XML data

– To avoid confusion with same element names

• Idea is to “prefix” each set of elements with a unique string• Typical GLOBALLY unique string is a URI

– http://www.karlwilcox.com/schemas/blazon/1.0

• Too long / messy to put in front of elements– So provide a “shorthand” prefix, unique to THIS document

<xml version=“1.0”xmlns:blazon=“http://www.karlwilcox.com/schemas/blazon/1.0”xmlns:xhtml=“xmlns="http://www.w3.org/1999/xhtml">

<xhtml:body>….<blazon:body>Information….</blazon:body>

XML Name Spaces - 2

• Having said all that…– Useful to know about namespaces

• But not always necessary:– Redefine your XML to avoid clashes – Rewrite your XML “on the fly” (e.g. use XSLT before merging)– Work out meaning from context

• We have 2 title elements – is this really a problem?– Is it simple to tell them apart?

<order><customer><title>Mr.</title><surname>Smith</surname>….<items><book><title>XML In a Nutshell</title><isbn>978-0-596—00764-5</isbn>…..

Moving on to Mobile Apps

• All the preceding discussion– Was about the development of websites specifically for mobiles

• Development of applications for mobiles is a different thing entirely– Apps are great (but NOT always necessary)– Is the Wikipedia app significantly more useful than the website?

Discuss!

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Developing Android Apps - 1

Developing Android Apps - 2

• App Inventor is not a toy!

• A lot of commonality with professional Android development environment– Approach to User Interface building– Attaching (Java) code to events– Desktop based emulator

• E.g. Eclipse “Indigo” with Android SDK– (See next slide)

TMA Tips: Project PlanningIn developing your app there are

several key-stages to follow:• Have a good understanding of

what is required• What is essential?• What are the nice haves?• Produce a Structured plan• Produce progression versions.• Critically appraise your work

Be prepared to start again!

TMA03: You are going to need• A stop watch to record

the running data• Access to a network• Access to the server to

upload the data

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TMA03: Possible Approach

• Start small, take small, incremental steps - E.g.

• Display a timer that updates every second

• Add a start button that starts the timer

• Add a stop button that stops the timer

• Add a reset button…. And so on

• Don’t try to build everything at once!

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TMA03: Notes

• Don’t get bogged down with App Inventor– 50% of the marks are for narrative answers in your report!

• Your App will be tested by me– So read “what to submit” very carefully

• Don’t try to do too much– Meeting the specification is sufficient

• Use sensible variable names / button labels etc.– Help me understand your app– It should NOT need a manual!

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Any Questions About TMA03?

Reminder about deadlines etc.

• TMA03 Deadline is noon 4th July– (Grace period to midnight, but no support available)– Make sure you understand what you need to submit!

• Block 4 available 2nd July– Will include part 1 of EMA – the work plan

• EMA materials available sometime in July– Work plan submission date 22nd August– Final submission date 26th September

• NO extensions for EMA (either part!)– Not from me anyway!– You can try student support but you will need a really good

reason!

Thank You For Attending!

• There will be a recording available in the elluminate room in a day or so

• Downloadable audio and video versions from http://karlwilcox.com/ou/tt284-13b a few days later

Thank you, and goodnight!