Start Developing iOS Apps Today

168 Pages·2015·10.16 MB·English

by  Apple Inc.

Start Developing iOS Apps Today
Contents
Introduction 6
Setup 7
GettheTools 8
ReviewaFewObjective-CConcepts 9
ObjectsAreBuildingBlocksforApps 9
ClassesAreBlueprintsforObjects 9
ObjectsCommunicateThroughMessages 9
ProtocolsDefineMessagingContracts 10
Tutorial: Basics 11
CreateaNewProject 13
GetFamiliarwithXcode 18
RuniOSSimulator 19
ReviewtheSourceCode 23
Themain.mFileandtheUIApplicationMainFunction 25
TheAppDelegateSourceFiles 26
OpenYourStoryboard 27
BuildtheBasicInterface 28
PreviewYourInterface 34
AdoptAutoLayout 37
Recap 42
Structuring an App 43
Defining the Concept 44
Designing a User Interface 45
TheViewHierarchy 45
TypesofViews 46
UseStoryboardstoLayOutViews 47
UseInspectorstoConfigureViews 50
UseAutoLayouttoPositionViews 51
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
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Contents
Defining the Interaction 54
ViewControllers 55
Actions 56
Outlets 56
Controls 56
NavigationControllers 57
UseStoryboardstoDefineNavigation 58
Tutorial: Storyboards 60
CreateaSecondScene 62
DisplayStaticContentinaTableView 66
AddaSeguetoNavigateForward 71
CreateCustomViewControllers 85
CreateanUnwindSeguetoNavigateBack 94
Recap 101
Implementing an App 102
Incorporating the Data 103
DesigningYourModel 103
ImplementingYourModel 104
IncorporatingRealData 104
Using Design Patterns 105
MVC 105
Target-Action 106
Delegation 107
Working with Foundation 108
ValueObjects 108
Strings 109
Numbers 110
CollectionObjects 111
Arrays 111
Sets 115
Dictionaries 115
RepresentingnilwithNSNull 117
Writing a Custom Class 119
DeclaringandImplementingaClass 120
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
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Contents
Interface 120
Implementation 120
PropertiesStoreanObject’sData 121
MethodsDefineanObject’sBehavior 122
MethodParameters 123
ImplementingMethods 124
Tutorial: Add Data 126
CreateaDataClass 128
LoadtheData 130
DisplaytheData 133
ToggleItemCompletionState 137
AddNewItems 140
Recap 149
Next Steps 150
iOS Technologies 151
UserInterface 151
Games 152
Data 152
Media 153
Finding Information 154
UseContextualHelpArticlesforXcodeGuidance 154
UseGuidesforGeneralandConceptualOverviews 156
UseAPIReferenceforClassInformation 158
UseQuickHelpforContextualSourceCodeInformation 162
UseSampleCodetoSeeReal-WorldUsage 164
Where to Go from Here 165
TakingtheToDoListApptotheNextLevel 166
Document Revision History 167
Objective-C 5
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4
Objective-CSwift
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
5
Introduction
● Setup (page 7)
● Tutorial:Basics (page 11)
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
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Setup
StartDevelopingiOSAppsToday istheperfectstartingpointforcreatingappsthatrunoniPad,iPhone,and
iPodtouch.Viewthisguide’sfourshortmodulesasagentleintroductiontobuildingyourfirstapp—including
thetoolsyouneedandthemajorconceptsandbestpracticesthatwilleaseyourpath.
Thefirstthreemodulesendwithatutorial,whereyou’llimplementwhatyou’velearned.Attheendofthelast
tutorial,you’llhavecreatedasimpleto-dolistapp.
Afteryoubuildyourfirstappandbeforeyoustartyournextendeavor,readthefourthmodule.Itexploresthe
technologiesandframeworksyoumightwanttoadopt.
Eventhoughittakesyouthrougheverystepofbuildingasimpleapp,tobenefitmostfromthisguide,ithelps
tobeacquaintedwithcomputerprogrammingingeneralandwithobject-orientedprogramminginparticular.
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
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Setup
GettheTools
Get the Tools
Beforeyoustartdevelopinggreatapps,setupadevelopmentenvironmenttoworkinandmakesureyou
havetherighttools.
TodevelopiOSapps,youneed:
● AMaccomputerrunningOSX10.9.4orlater
● Xcode(latestversion)
● iOSSDK
XcodeisApple’sintegrateddevelopmentenvironment(IDE).Xcodeincludesasourceeditor,agraphicaluser
interfaceeditor,andmanyotherfeatures.TheiOSSDKextendsXcodetoincludethetools,compilers,and
frameworksyouneedspecificallyforiOSdevelopment.
DownloadthelatestversionofXcodeonyourMacforfreefromtheAppStore.TheiOSSDKisincludedwith
Xcode.
TodownloadthelatestversionofXcode
1. OpentheAppStoreapponyourMac(bydefaultit’sintheDock).
2. Inthesearchfieldinthetop-rightcorner,typeXcodeandpresstheReturnkey.
3. ClickFree .
Xcodeisdownloadedintoyour/Applicationsdirectory.
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
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Setup
ReviewaFewObjective-CConcepts
Review a Few Objective-C Concepts
Asyouwritecodeinthetutorials,you’llbeworkingwiththeObjective-Cprogramminglanguage.Objective-C
isbuiltontopoftheCprogramminglanguageandprovidesobject-orientedcapabilitiesandadynamicruntime.
Yougetallofthefamiliarelements,suchasprimitivetypes(int,float,andsoon),structures,functions,
pointers,andcontrolflowconstructs(while,if...else,andforstatements).Youalsohaveaccesstothe
standardClibraryroutines,suchasthosedeclaredinstdlib.handstdio.h.
Objects Are Building Blocks for Apps
WhenyoubuildaniOSapp,mostofyourtimeisspentworkingwithobjects.
Objectspackagedatawithrelatedbehavior.Anappisalargeecosystemofinterconnectedobjectsthat
communicatewitheachothertoperformspecifictasks,suchasdisplayingavisualinterface,respondingto
userinput,andstoringinformation.Youusemanydifferenttypesofobjectstobuildyourapp,rangingfrom
interfaceelements,suchasbuttonsandlabels,todataobjects,suchasstringsandarrays.
Classes Are Blueprints for Objects
Aclassdescribesthebehaviorandpropertiescommontoanyparticulartypeofobject.
Inthesamewaythatmultiplebuildingsconstructedfromthesameblueprintareidenticalinstructure,every
instanceofaclasssharesthesamepropertiesandbehaviorasallotherinstancesofthatclass.Youcanwrite
yourownclassesoruseframeworkclassesthathavebeendefinedforyou.
Youmakeanobjectbycreatinganinstanceofaparticularclass.Youdothisbyallocatingtheobjectand
initializingitwithacceptabledefaultvalues.Whenyouallocateanobject,yousetasideenoughmemoryfor
theobjectandsetallinstancevariablestozero.Initializationsetsanobject’sinitialstate—thatis,itsinstance
variablesandproperties—toreasonablevaluesandthenreturnstheobject.Thepurposeofinitializationisto
returnausableobject.Youneedtobothallocateandinitializeanobjecttobeabletouseit.
AfundamentalconceptinObjective-Cprogrammingisclassinheritance,theideathataclassinheritsbehaviors
fromaparentclass.Whenoneclassinheritsfromanother,thechild—orsubclass—inheritsallthebehavior
andpropertiesdefinedbytheparent.Thesubclasscandefineitsownadditionalbehaviorandpropertiesor
overridethebehavioroftheparent.Thusyoucanextendthebehaviorsofaclasswithoutduplicatingitsexisting
behavior.
Objects Communicate Through Messages
Objectsinteractbysendingeachothermessagesatruntime.InObjective-Cterms,oneobjectsendsamessage
toanotherobjectbycallingamethodonthatobject.
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
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Setup
ReviewaFewObjective-CConcepts
AlthoughthereareseveralwaystosendmessagesbetweenobjectsinObjective-C,byfarthemostcommon
isthebasicsyntaxthatusessquarebrackets.IfyouhaveanobjectsomePersonofclassXYZPerson,youcan
senditthesayHellomessagelikethis:
[somePerson sayHello];
Thereferenceontheleft,somePerson,isthereceiverofthemessage.Themessageontheright,sayHello,
isthenameofthemethodtocallonthatreceiver.Inotherwords,whentheabovelineofcodeisexecuted,
somePersonwillbesentthesayHellomessage.
Protocols Define Messaging Contracts
Aprotocoldefinesasetofbehaviorsthatareexpectedofanobjectinagivensituation.Aprotocolcomesin
theformofaprogrammaticinterface,onethatanyclassmayimplement.Usingprotocols,twoclassesdistantly
relatedbyinheritancecancommunicatewitheachothertoaccomplishacertaingoal,suchasparsingXML
codeorcopyinganobject.
Anyclassthatcanprovideusefulbehaviortootherclassescandeclareaprogrammaticinterfaceforvending
thatbehavioranonymously.Anyotherclasscanchoosetoadopttheprotocolandimplementoneormoreof
theprotocol’smethods,makinguseofthebehavior.
2015-03-09 | Copyright © 2015 Apple Inc. All Rights Reserved.
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