Sams creating vista gadgets using HTML CSS and javascript with examples in RSS AJAX activex COM and silverlight may 2008 ISBN 0672329689

CreatingVista®Gadgets:UsingHTML,CSSand
JavaScriptwithExamplesinRSS,Ajax,ActiveX
(COM)andSilverlight™
byRajeshLal
Publisher:Sams
PubDate:May05,2008
PrintISBN-10:0-672-32968-9
PrintISBN-13:978-0-672-32968-5
Pages:360
TableofContents|Index

Overview
Aone-stopresourceforeachaspectofdesigningand
developingSidebargadgets,perfectforanyonewhowantsto
createkillergadgets
ExploresoneofthesupercoolfeaturesnewtoWindows
Vista--theSidebar
Itisaone-stopresourceforeachaspectofdesigningand
developingSidebargadgets,perfectforanyonewhowants
tocreatekillergadgets
Includescompletedesigninstructionsforfournever-beforeseengadgets
WindowsVistaSidebarisapanellocatedonthedesktopofaPC
wheregadgetscanbeplacedforeasyaccessandreference.
Thesegadgetsaresmall,single-purposeapplications,suchas
clocks,calendars,games,RSSnotifiers,searchtools,stock
tickers,etc,thatresideontheWindowsdesktopandonthe
WindowsSidebar.Thebookwillbeatutorialtodesignand
developagadget.Itwillprovideready-to-usesamplesusing
.NET,XML,CSSandAJAX.Afterreadingthebook,aweb
developer/designerwillbeconfidentenoughtostartdeveloping

gadgetsforWindowsVistaSidebar.Thebeginnerportionofthe
bookshowsanoverviewofthesubjectwiththedesignpattern,
thearchitectureandimplementationdetails.Thelatersections
willhavesolidexamplesforinstantresults.Inshort,thebook
willtellhowtodoeverythingwithSidebarGadgetsusingsolid,
uniqueexamples.Briefoutline:"BriefbackgroundonGadgets"
Definearchitecture,designconsiderationandimplementationto
giveaclearviewtothedeveloper"Stepbystep,createa
usefulGadgetsample"MyBlogs""Elaboratethearchitecture
designconstraintandimplementationdetailsforthesample"
Detailthestandardpractices"Recheckthegadgetcreatedfor
standardpractices"ImproviseandImprovewithcompareand
contrast"Addadvancedsampleswith.NET,AJAXandXHTML.


CreatingVista®Gadgets:UsingHTML,CSSand
JavaScriptwithExamplesinRSS,Ajax,ActiveX
(COM)andSilverlight™
byRajeshLal
Publisher:Sams
PubDate:May05,2008
PrintISBN-10:0-672-32968-9
PrintISBN-13:978-0-672-32968-5
Pages:360
TableofContents|Index

Copyright
AbouttheAuthor
Acknowledgement

WeWanttoHearfromYou!
ReaderServices
Introduction
What'sintheBook
SpecialFeaturesandNotations
SupportingWebsite
PartI:TheFoundation
Chapter1.InnovatewithWindowsVistaSidebarGadgets
IntroducingGadgetsandtheVistaSidebar
InnovatewithGadgets
GadgetsinDepth
MultiplePlatformsforGadgets
Chapter2.TheArchitecture
GadgetsOverview
TechnologyBehindGadgetDevelopment
GadgetObjectModel
SidebarGadgets:TheRoadAhead
Chapter3.AnApproachtoDesign


DesignConsiderations
ChallengesfortheUserInterface
VisualThemes
TransparentImagesintheGadget
AboutAccessibility
Chapter4.SellingYourGadget
GadgetRevenueModel
HowGadgetsGiveYouBusiness
SupportingYourGadget
PartII:DevelopingaGadget

Chapter5.CreatingaSimpleGadgetwithRSS/AtomFeed
FeedGadgets
BasicFrameworkoftheMyBlogGadget
HowtheMyBlogGadgetWorks
PartsoftheMyBlogGadget
Chapter6.DesignPatternsandStandardPractices
DesignPatterns
ElementsofDesignPatterns
CommonAssumptions
AddingAccessibility
Chapter7.TheMyBlogGadgetRevisited
RecappingtheMyBlogGadget
TakingtheMyBlogGadgettotheNextLevel
Docked,Undocked,andMiniMeVersion
Chapter8.DebuggingandDeployingaGadget
DebuggingaGadget
DeployingaGadget
DeploymentUsingaCabinetFile
PartIII:AdvancedSamples
Chapter9.SiteStatisticsGadgetwithAjax—AnInformation
Gadget
TheGoal


FeaturesandTechnology
DesignConsiderations
DevelopingtheGadget
Chapter10.MostRecentUsed.NETProjects—AnApplication
Gadget
Recent.NETProjectGadget

FeaturesandTechnology
DesignConsiderations
DevelopingtheGadget
Chapter11.RadioGadgetandYouTubeVideoGadget—Fun
Gadgets
MediaGadgets
TheRadioGadget
TheYouTubeVideoGadget
Chapter12.SilverlightWorldClock—UtilityGadget
TheSilverlightGadget
DesignConsiderations
DevelopingtheGadget
CreatingaSidebarGadgetUsingMicrosoftPopfly
WheretoGofromHere
PartIV:Appendixes
AppendixA.TipsandTricks
AutomaticUpdateandUserTracking
ReadingXML,XHTML,RSS/Atom,HTML,Text,andJSON
Data
GlobalizationandLocalization
GraphicDesign
SecurityandOtherResources
AppendixB.Extras
ReusableFrameworkforCreatingGadgets
SampleGadgetsBasedontheFramework
ShareYourGadgets


Index

Copyright
CreatingVista®Gadgets:UsingHTML,CSSandJavaScript
withExamplesinRSS,AJAX,ActiveX(COM)and
Silverlight™
Copyright©2008bySamsPublishing
Allrightsreserved.Nopartofthisbookshallbereproduced,
storedinaretrievalsystem,ortransmittedbyanymeans,
electronic,mechanical,photocopying,recording,orotherwise,
withoutwrittenpermissionfromthepublisher.Nopatent
liabilityisassumedwithrespecttotheuseoftheinformation
containedherein.Althougheveryprecautionhasbeentakenin
thepreparationofthisbook,thepublisherandauthorassume
noresponsibilityforerrorsoromissions.Norisanyliability
assumedfordamagesresultingfromtheuseoftheinformation
containedherein.
Thismaterialmaybedistributedonlysubjecttothetermsand
conditionssetforthintheOpenPublicationLicense,v1.0or
later(thelatestversionispresentlyavailableat
/>ISBN-13:978-0-672-32968-5
LibraryofCongressCataloging-in-PublicationData

Lal,Rajesh.
CreatingVistagadgets:usinghtml,cssandjavascriptwithexamples
inrss,ajax,activex(com)andsilverlight/RajeshLal.
p.cm.
ISBN978-0-672-32968-5(pbk.)
1.MicrosoftWindows(Computerfile)2.Operatingsystems(Computers)
3.Userinterfaces(Computersystems)I.Title.
QA76.76.O63L35462008

005.4'46--dc22
2008016280


PrintedintheUnitedStatesofAmerica
FirstPrintingApril2008
AssociatePublisher
GregWiegand
AcquisitionsEditor
LorettaYates
DevelopmentEditor
ToddBrakke
ManagingEditor
PatrickKanouse
ProjectEditor
JenniferGallant
CopyEditor
MargoCatts
Indexer
KenJohnson
Proofreader
MikeHenry
TechnicalEditor
MarcClifton
PublishingCoordinator
CindyTeeters
BookDesigner
AnneJones

Trademarks

Alltermsmentionedinthisbookthatareknowntobe
trademarksorservicemarkshavebeenappropriately
capitalized.SamsPublishingcannotattesttotheaccuracyof
thisinformation.Useofaterminthisbookshouldnotbe
regardedasaffectingthevalidityofanytrademarkorservice
mark.

WarningandDisclaimer
Everyefforthasbeenmadetomakethisbookascompleteand
asaccurateaspossible,butnowarrantyorfitnessisimplied.
Theinformationprovidedisonan"asis"basis.Theauthorand
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Dedication
DedicatedtoMom&Dad

ForEverythingIAm


AbouttheAuthor
RajeshLalisanauthor,technologyevangelist,andsolutions
engineerspecializinginwebtechnologies.Hehasreceived
numerousawardsforhisarticlesonWindowsVistaandSidebar
Gadgets.HeisafrequentcontributortoWindowsVista
MagazineandCodeProjectwebsites.Withmorethanadecade
ofexperienceinITindustryinprogressiverolesfromgraphic
designer,softwaredeveloper,architect,teamlead,andproject
leadertoindependentconsultant,Rajeshenjoystakingan
objectiveandpragmaticapproachtodevelopingapplications
usingMicrosofttechnology.Hehasamaster'sdegreein
computerscienceandholdsMCSDandMCADtitles.
ToreadhisVistaGadgetblog,goto
www.innovatewithgadgets.com.


Acknowledgement
Writingisafascinatingjourney.Iwouldliketoextendmy
specialthankstoMarcCliftonToddBrakke,andMargoCatts
whowerealongwithmeonthisjourney.Theycorrected,
annotated,criticized,andhelpedmeateverystep.Thanksalso
toJoshuaHeyer(Shog9)andRamaKrishnaforreviewingthis
bookandfortheirinvaluableadvice.Ialsowanttoaddanote
ofthankstoDr.Luijiforalltheencouragementatthetimes
whenIneededit.
IamdeeplygratefultoLorettaYates,acquisitionseditorat
Sams/QuePublishingforherunmatcheddedicationtoquality

andprogressiveness,withoutwhichthisbookwasnever
possible.ThanksalsotoJenniferGallant,CindyTeeters,and
RosemaryLewisfromPearsonTechnologyGroup.
Iwouldliketoextendmyappreciationtothefolksfrom
Microsoft,fortheirtimeandefforttomakethisbookcomplete
ineverysense,especiallyBrianTeutsch,DanielMoth,and
AnnuskaPerkins.IwouldalsoliketothankRickKingslan,Karen
Wong,andMarkSchmidt.
Lastofall,IwouldliketomentionmybrothersRakeshand
Rajeev,forallthewonderfulthingsIhavelearnedfromthem,
andSimpleandShilpiforjustbeingsowonderful.Andmy
inspirationandmydrivingforceNeelu.


WeWanttoHearfromYou!
Asthereaderofthisbook,youareourmostimportantcritic
andcommentator.Wevalueyouropinionandwanttoknow
whatwe'redoingright,whatwecoulddobetter,whatareas
you'dliketoseeuspublishin,andanyotherwordsofwisdom
you'rewillingtopassourway.
Youcanemailorwritemedirectlytoletmeknowwhatyoudid
ordidn'tlikeaboutthisbook—aswellaswhatwecandoto
makeourbooksstronger.
PleasenotethatIcannothelpyouwithtechnicalproblems
relatedtothetopicofthisbook,andthatduetothehigh
volumeofmailIreceive,Imightnotbeabletoreplytoevery
message.
Whenyouwrite,pleasebesuretoincludethisbook'stitleand
authoraswellasyournameandphoneoremailaddress.Iwill
carefullyreviewyourcommentsandsharethemwiththeauthor

andeditorswhoworkedonthebook.
Email:



Mail:

GregWiegand
AssociatePublisher
SamsPublishing
800East96thStreet
Indianapolis,IN46240USA


ReaderServices
Visitourwebsiteandregisterthisbookatinformit.com/register
forconvenientaccesstoanyupdates,downloads,orerratathat
mightbeavailableforthisbook.


Introduction
WiththebroadesteverworldwidereleaseofaPCoperating
system,in2007WindowsVistaopenedthedoortoaneraof
gadgetdevelopment.Gadgets,whichresideontheWindows
VistaSidebar,aresmall,lightweight,andcanbeveryuseful
applications.TheSidebarisabrandnewplatformforinnovation
anditgivesusersauniquewaytointeractwithinformation.
Thisbookisforpeoplewhowanttocreatefeature-richand
professional-lookingVistaSidebargadgets.It'saguidefor
designers,developers,andanyoneelsewhohasabasic

knowledgeofHTML,CSS,andJavaScriptandwantstoleverage
thisnewandinnovativeplatform.It'sforanyonewhowantsto
createagadgetforhiscompany,orforaprogrammerwitha
greatideatoimplementonaSidebargadgetplatform,oreven
forahobbyistprogrammer,whowantstotryhishandona
gadgetplatform.Thisbookisintendedtogiveyouideasfor
whatyoucandowiththisnewplatformandhowyoucandoit.

What'sintheBook
Thisbookstartswithabriefbackgroundongadgets,andthen
givesabroadandclearviewofthearchitectureofgadget
development.Gadgetdesignconsiderationsareanimportant
partofthisbookandtheygosidebysidewithalmostallthe
chaptersthatdealwithgadgetdevelopment.Onceyou'veread
upontheconceptandscopeofgadgetdevelopment,thebook
helpsyoucreateagadgetcalledMyBlog.Duringthisprocess
thetextelaboratesonthearchitecture,designconstraints,and
implementationdetailsforthegadgetandthendetailssome
standardpracticesapplicabletoallgadgetdevelopment.The
lastsectiondealswithmoreadvancedgadgetexamplesthat
utilize.NET,XML,XHTML,CSS,Ajax,andMicrosoftSilverlight.
Thisbookisdividedintothreebroadsections.

Section1:TheFoundation


Thefourchaptersinthisfirstsectiongiveathorough
backgroundofSidebargadgets.Thesectionexplainsthetypes
ofgadgets,thearchitecture,andthetechnologybehindthe
gadgetdevelopment.The"ApproachtoDesign"chapterhelps

youknowthedifferencebetweenamerelygood-lookinggadget
andaonethatisprofessional,rich,andworththespaceit
takesupontheuser'sdesktop.Thelastchapterdiscussesthe
revenuemodelofthegadget:whatyouneedtoknowtosell
yourgadgets.

Section2:DevelopingaGadget
Thissectionwalksyouthroughthestandarddevelopment
processofagadget.ItdetailsthecreationofthebasicMyBlog
Gadget,whichmakesuseofanRSS/Atomfeed.Italsogoes
throughbestpracticeswiththeuserinterface,design
guidelines,andcommonassumptions.Thelaterchapters
improveonthebasicgadgetbasedonstandardpracticesand
alsodealwithdeployinganddistributingagadget.

Section3:AdvancedSamples
Thesectiondealswithadvancedsamples.Youwillbeableto
createadvancedgadgetssuchasaSiteStatisticsGadget,a
RadioGadget,andaYouTubeVideoGadget.Allthesamples
followstandardpatterns,makingiteasiertoswitchbetweenthe
featuresandfunctionalityyouwant,whenyouwant.Youwill
alsolearnhowtouseActiveXCOMforcreatingautilitygadget
withasample.NetMostRecentUsed(MRU)Gadget.Thefinal
chaptershowsyouhowtocreateagadgetwithMicrosoft
Silverlight.Youwillalsoseehow,injustafewminutes,to
createaSidebargadgetwithMicrosoftPopfly.
Ifyouarearelativelynewgadgetdeveloper,Iwouldsuggest
youtostartwiththefirstsection.Ifyouhavebasicbackground
knowledgeofgadgetsandyoujustwanttostartwiththestepby-steppracticalapproachtogadgetdevelopment,youcan
directlystartwiththesecondsection,"DevelopingaGadget."

Thethirdsection,"AdvancedSamples,"isforpeoplewhohave


developedagadgetandwanttogobeyondthebasicsofgadget
development.Eachchapterinthethirdsectionisactuallyan
advancedsampledealingwithaparticulartypeofgadgetina
scenarioofitsown.


Introduction
WiththebroadesteverworldwidereleaseofaPCoperating
system,in2007WindowsVistaopenedthedoortoaneraof
gadgetdevelopment.Gadgets,whichresideontheWindows
VistaSidebar,aresmall,lightweight,andcanbeveryuseful
applications.TheSidebarisabrandnewplatformforinnovation
anditgivesusersauniquewaytointeractwithinformation.
Thisbookisforpeoplewhowanttocreatefeature-richand
professional-lookingVistaSidebargadgets.It'saguidefor
designers,developers,andanyoneelsewhohasabasic
knowledgeofHTML,CSS,andJavaScriptandwantstoleverage
thisnewandinnovativeplatform.It'sforanyonewhowantsto
createagadgetforhiscompany,orforaprogrammerwitha
greatideatoimplementonaSidebargadgetplatform,oreven
forahobbyistprogrammer,whowantstotryhishandona
gadgetplatform.Thisbookisintendedtogiveyouideasfor
whatyoucandowiththisnewplatformandhowyoucandoit.

What'sintheBook
Thisbookstartswithabriefbackgroundongadgets,andthen
givesabroadandclearviewofthearchitectureofgadget

development.Gadgetdesignconsiderationsareanimportant
partofthisbookandtheygosidebysidewithalmostallthe
chaptersthatdealwithgadgetdevelopment.Onceyou'veread
upontheconceptandscopeofgadgetdevelopment,thebook
helpsyoucreateagadgetcalledMyBlog.Duringthisprocess
thetextelaboratesonthearchitecture,designconstraints,and
implementationdetailsforthegadgetandthendetailssome
standardpracticesapplicabletoallgadgetdevelopment.The
lastsectiondealswithmoreadvancedgadgetexamplesthat
utilize.NET,XML,XHTML,CSS,Ajax,andMicrosoftSilverlight.
Thisbookisdividedintothreebroadsections.

Section1:TheFoundation


Thefourchaptersinthisfirstsectiongiveathorough
backgroundofSidebargadgets.Thesectionexplainsthetypes
ofgadgets,thearchitecture,andthetechnologybehindthe
gadgetdevelopment.The"ApproachtoDesign"chapterhelps
youknowthedifferencebetweenamerelygood-lookinggadget
andaonethatisprofessional,rich,andworththespaceit
takesupontheuser'sdesktop.Thelastchapterdiscussesthe
revenuemodelofthegadget:whatyouneedtoknowtosell
yourgadgets.

Section2:DevelopingaGadget
Thissectionwalksyouthroughthestandarddevelopment
processofagadget.ItdetailsthecreationofthebasicMyBlog
Gadget,whichmakesuseofanRSS/Atomfeed.Italsogoes
throughbestpracticeswiththeuserinterface,design

guidelines,andcommonassumptions.Thelaterchapters
improveonthebasicgadgetbasedonstandardpracticesand
alsodealwithdeployinganddistributingagadget.

Section3:AdvancedSamples
Thesectiondealswithadvancedsamples.Youwillbeableto
createadvancedgadgetssuchasaSiteStatisticsGadget,a
RadioGadget,andaYouTubeVideoGadget.Allthesamples
followstandardpatterns,makingiteasiertoswitchbetweenthe
featuresandfunctionalityyouwant,whenyouwant.Youwill
alsolearnhowtouseActiveXCOMforcreatingautilitygadget
withasample.NetMostRecentUsed(MRU)Gadget.Thefinal
chaptershowsyouhowtocreateagadgetwithMicrosoft
Silverlight.Youwillalsoseehow,injustafewminutes,to
createaSidebargadgetwithMicrosoftPopfly.
Ifyouarearelativelynewgadgetdeveloper,Iwouldsuggest
youtostartwiththefirstsection.Ifyouhavebasicbackground
knowledgeofgadgetsandyoujustwanttostartwiththestepby-steppracticalapproachtogadgetdevelopment,youcan
directlystartwiththesecondsection,"DevelopingaGadget."
Thethirdsection,"AdvancedSamples,"isforpeoplewhohave


developedagadgetandwanttogobeyondthebasicsofgadget
development.Eachchapterinthethirdsectionisactuallyan
advancedsampledealingwithaparticulartypeofgadgetina
scenarioofitsown.


SpecialFeaturesandNotations
Thisbookismeanttobeadefinite,precise,andconcreteguide

forgadgetdevelopment.Bypruningredundantinformationand
filteringandhighlightingtheinformationthatismorecrucial,
wehavetriedtomakeitascomprehensiveaspossible.This
bookincludesvariousfeaturesandconventionsthathelpyou
getthemostoutofthebook.
HTML,CSS,andJavaScriptcodeblockswillbeshownas
follows:
90
<HTML>
CodeinHTML,CSS,andJavaScript
</HTML>

Samplesinglecodelineswilllooklikethis:
90

Statementone;
Statementtwo;

Othercommentswillalsoshowupinthecodewithtwo
backslashes
90

//Commentone


//Commenttwo

Thebookalsousesthefollowingboxesforimportant
information:
Note

ANoteincludesextrainformationtobroadenyour
understandingofatopic.

Tip
ATipprovidesalternative,shortcuts,orinsider
informationofthetopicbeingdiscussed.

Caution
ACautionwarnsyouofpotentialtrapsandpitfalls.


SupportingWebsite
Thebookhasasupportingwebsitewhereyoucandownloadall
thecodesandgadgets.ThewebsitealsohasblogsIhave
writtenonSidebargadgetsandsomeofmypersonalviewson
gadgetdevelopment.Youareinvitedtocheckthatsiteand
contactmepersonally.Youwillalsofinderrataandmost
updatedinformationthere.
Visitwww.innovatewithgadgets.com


PartI:TheFoundation
InThisPart

CHAPTER1InnovatewithWindowsVista
SidebarGadgets

CHAPTER2TheArchitecture
CHAPTER3AnApproachtoDesign
CHAPTER4SellingYourGadget


Chapter1.InnovatewithWindowsVista
SidebarGadgets
"...theonlyreasontoinvestincompaniesinthefutureis
theirabilitytoinnovate...
—JeffreyImmelt,CEO,GE
INTHISCHAPTER
IntroducingGadgetsandtheVistaSidebar
InnovatewithGadgets
GadgetsinDepth
MultiplePlatformsforGadgets

IntroducingGadgetsandtheVista
Sidebar
Formanypeople,Sidebargadgetsarethecoolestnewfeature
intheWindowsVistaoperatingsystem.Gadgetsaresmall,
lightweightapplicationsthatresideontheWindowsVista
SidebarorWindowsVistadesktop.Theyprovideready-to-use
informationandeasyaccesstofrequentlyusedfeaturesand
tools.
Gadgetsofferadiverserangeoffunctionality,fromgivingyou
anat-a-glanceviewofyourupcomingappointments,tolisting
onlinecontacts,todisplayingapictureslideshowofyourFlickr
account,toofferinganeasywaytocontrolyourmediaplayer.
Gadgetscanhaveanynumberofdedicatedpurposes.Asshown
inFigure1.1,theycanbeclocks,calculators,games,sticky

notes,andmore.
Figure1.1.GadgetscanbeplacedanywhereontheVista
desktop,butmostareorganizedontheWindows
Sidebar.


WindowsSidebar
TheWindowsSidebarisapaneonthesideoftheMicrosoft
WindowsVistadesktopandisusedtoplaceandorganizethe
gadgets.YoucaneasilycustomizetheWindowsSidebartosuit
yourpreference:alwaysontoporrestingbelowmaximized
windows.Ifyoudon'twanttokeepyourgadgetsonthe
WindowsSidebar,youcandragthemtoyourdesktopandhide
theSidebar.TheWindowsSidebarcanalsobeactivatedfrom
theiconinthesystemtray.
Gadgetscanhavemultipleinstances,bothintheSidebaras
wellasontheWindowsdesktop,andthesecanbeconfigured
withdifferentsettings.Forexample,youcanhavetwo
instancesofaClockGadget,oneshowingthecurrenttimefor
SanDiego,CaliforniaandtheotheroneforParis,France.
AVistaSidebargadgetconsistsofHTML,CSS,JavaScript,and
imagefiles,allcoordinatedtoaccomplishavarietyoftasks.You
canhostaminiwebpage,callawebservice,integratewitha
businessapplication,orevencalloperatingsystemAPIsto
createacustomapplication.

TechnologyBehindGadgets
Gadgetsaredevelopedusingstandardwebtechnologies,
namelyHTML,CSS,andJavaScript,buttheycanalsouse