iOS 8 Swift Programming Cookbook Solutions & Examples for iOS Apps

901 Pages·2014·23.51 MB·English

by  Vandad Nahavandipoor

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iOS 8 Swift Programming Cookbook c
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Entirely rewritten for Apple’s Swift programming language, this updated “ From coding with new CPiO 6
cookbook helps you overcome the vexing issues you’re likely to face when iOS features to tackling or
creating apps for iOS devices. oS
complex requirements, o
You’ll find hundreds of new and revised recipes for using the iOS 8 SDK, g
Vandad's iOS k 8
including techniques for working with Health app data and HomeKit
accessories, enhancing and animating graphics, storing and protecting Programming Cookbook br
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data, sending and receiving notifications, and managing files and folders. always provides me with
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Each recipe includes sample code on GitHub that you can use right away. the resources I need and mw
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good, clear, practical
■ Use CloudKit APIs to store information in the cloud with ease kmi
examples. Now that I'm f
■ Create custom keyboards and extensions t
starting out using Swift, i
■ Access users’ health-related information with HealthKit n
this edition is my Bible—I'd
■ Interact with accessories inside the user’s home with HomeKit
have been lost without it.” g
■ Create vibrant and lifelike user interfaces with UIKit Dynamics
—João Duarte
■ Use the Keychain to protect your app’s data
Senior iOS Software Engineer
■ Develop location-aware and multitasking-aware apps
iOS 8 Swift
■ Work with iOS 8’s audio and video APIs
■ Use Event Kit UI to manage calendars, dates, and events
■ Take advantage of the accelerometer and the gyroscope
■ Get working examples for implementing gesture recognizers
P rogramming
■ Retrieve and manipulate contacts and groups from the
Address Book
■ Determine a camera’s availability and access the Photo Library
C ookbook
Vandad Nahavandipoor is an iOS and OS X programmer for an international
N
media group with over 7,000 employees in more than 29 countries. Previously
a
he worked for Lloyds Banking Group in England to deliver their iOS apps to millions h
a
of users in the UK. v
a
n
d
ip
o SOLUTIONS & EXAMPLES FOR IOS APPS
o
r
MOBILE DEVELOPMENT/IOS Twitter: @oreillymedia
facebook.com/oreilly
US $59.99 CAN $62.99
ISBN: 978-1-491-90869-3
Vandad Nahavandipoor
C
o
v
e
r
s
X
iOS 8 Swift Programming Cookbook c
o
d
e
Entirely rewritten for Apple’s Swift programming language, this updated “ From coding with new CPiO 6
cookbook helps you overcome the vexing issues you’re likely to face when iOS features to tackling or
creating apps for iOS devices. oS
complex requirements, o
You’ll find hundreds of new and revised recipes for using the iOS 8 SDK, g
Vandad's iOS k 8
including techniques for working with Health app data and HomeKit
accessories, enhancing and animating graphics, storing and protecting Programming Cookbook br
aS
data, sending and receiving notifications, and managing files and folders. always provides me with
o
Each recipe includes sample code on GitHub that you can use right away. the resources I need and mw
o
good, clear, practical
■ Use CloudKit APIs to store information in the cloud with ease kmi
examples. Now that I'm f
■ Create custom keyboards and extensions t
starting out using Swift, i
■ Access users’ health-related information with HealthKit n
this edition is my Bible—I'd
■ Interact with accessories inside the user’s home with HomeKit
have been lost without it.” g
■ Create vibrant and lifelike user interfaces with UIKit Dynamics
—João Duarte
■ Use the Keychain to protect your app’s data
Senior iOS Software Engineer
■ Develop location-aware and multitasking-aware apps
iOS 8 Swift
■ Work with iOS 8’s audio and video APIs
■ Use Event Kit UI to manage calendars, dates, and events
■ Take advantage of the accelerometer and the gyroscope
■ Get working examples for implementing gesture recognizers
P rogramming
■ Retrieve and manipulate contacts and groups from the
Address Book
■ Determine a camera’s availability and access the Photo Library
C ookbook
Vandad Nahavandipoor is an iOS and OS X programmer for an international
N
media group with over 7,000 employees in more than 29 countries. Previously
a
he worked for Lloyds Banking Group in England to deliver their iOS apps to millions h
a
of users in the UK. v
a
n
d
ip
o SOLUTIONS & EXAMPLES FOR IOS APPS
o
r
MOBILE DEVELOPMENT/IOS Twitter: @oreillymedia
facebook.com/oreilly
US $59.99 CAN $62.99
ISBN: 978-1-491-90869-3
Vandad Nahavandipoor
iOS 8 Swift Programming
Cookbook
Vandad Nahavandipoor
iOS 8 Swift Programming Cookbook
by Vandad Nahavandipoor
Copyright © 2015 Vandad Nahavandipoor. All rights reserved.
Printed in the United States of America.
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ISBN: 978-1-491-90869-3
[Malloy]
Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
1. The Basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1. Adding Blur Effects to Your Views 9
1.2. Presenting Temporary Information on the Screen with Popovers 12
1.3. Displaying Images with UIImageView 17
1.4. Displaying Static Text with UILabel 21
1.5. Adding Buttons to the User Interface with UIButton 27
1.6. Displaying Alerts and Action Sheets 31
1.7. Creating, Using, and Customizing Switches with UISwitch 37
1.8. Picking Values with the UIPickerView 41
1.9. Picking the Date and Time with UIDatePicker 46
1.10. Implementing Range Pickers with UISlider 49
1.11. Grouping Compact Options with UISegmentedControl 53
1.12. Presenting Sharing Options with UIActivityViewController 57
1.13. Presenting Custom Sharing Options with UIActivityViewController 63
1.14. Displaying an Image on a Navigation Bar 68
1.15. Adding Buttons to Navigation Bars Using UIBarButtonItem 70
1.16. Accepting User Text Input with UITextField 75
1.17. Displaying Long Lines of Text with UITextView 83
1.18. Creating Scrollable Content with UIScrollView 88
1.19. Loading Web Pages with WebKit 91
1.20. Loading Web Pages with UIWebView 94
1.21. Displaying Progress with UIProgressView 97
1.22. Creating a Provision Profile 99
2. Extensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
2.1. Adding New Photo Editing Capabilities to the Photos App 110
2.2. Providing a Custom Sharing Extension to iOS 118
iii
2.3. Building Custom Keyboards 129
2.4. Creating a Service Within Your App with Action Extensions 137
2.5. Adding Widgets to the Notification Center 144
3. Managing Health Data with HealthKit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
3.1. Setting Up Your App for HealthKit 155
3.2. Retrieving and Modifying the User’s Weight Information 160
3.3. Accessing and Modifying the User’s Height Information 165
3.4. Retrieving User Characteristics 172
3.5. Observing Changes to the User’s Health Information 177
3.6. Reading and Modifying the User’s Total Calories Burned 183
3.7. Converting Between Units 196
4. Managing Home Appliances with HomeKit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
4.1. Simulating HomeKit Accessories 203
4.2. Managing the User’s Home in HomeKit 212
4.3. Adding Rooms to the User’s Home 219
4.4. Specifying Zones in the User’s Home 224
4.5. Discovering and Managing HomeKit Enabled Accessories 229
4.6. Interacting with HomeKit Accessories 234
4.7. Grouping Services of HomeKit Accessories 242
5. Creating Dynamic and Interactive User Interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
5.1. Adding Gravity to Your UI Components 249
5.2. Detecting and Reacting to Collisions Between UI Components 250
5.3. Animating Your UI Components with a Push 257
5.4. Attaching Multiple Dynamic Items to Each Other 262
5.5. Adding a Dynamic Snap Effect to Your UI Components 266
5.6. Assigning Characteristics to Your Dynamic Effects 269
6. Table and Collection Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
6.1. Populating a Table View with Data 277
6.2. Enabling Swipe Deletion of Table View Cells 281
6.3. Constructing Headers and Footers in Table Views 282
6.4. Displaying a Refresh Control for Table Views 288
6.5. Providing Basic Content to a Collection View 292
6.6. Feeding Custom Cells to Collection Views Using .xib Files 297
6.7. Handling Events in Collection Views 303
6.8. Providing Header and Footer in a Collection View 307
6.9. Adding Custom Interactions to Collection Views 312
iv | Table of Contents
7. Concurrency and Multitasking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
7.1. Performing UI-Related Tasks 319
7.2. Performing Non-UI Related Tasks 321
7.3. Performing Tasks After a Delay 329
7.4. Performing a Task Only Once 331
7.5. Grouping Tasks Together 332
7.6. Creating Simple Concurrency with Operations 335
7.7. Creating Dependency Between Operations 340
7.8. Firing Periodic Tasks 342
7.9. Completing a Long-Running Task in the Background 345
7.10. Adding Background Fetch Capabilities to Your Apps 348
7.11. Playing Audio in the Background 357
7.12. Handling Location Changes in the Background 360
7.13. Handling Network Connections in the Background 363
8. Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
8.1. Authenticating the User with Touch ID 373
8.2. Enabling Security and Protection for Your Apps 376
8.3. Storing Values in the Keychain 381
8.4. Finding Values in the Keychain 383
8.5. Updating Existing Values in the Keychain 386
8.6. Deleting Existing Values in the Keychain 390
8.7. Sharing Keychain Data Between Multiple Apps 392
8.8. Writing to and Reading Keychain Data from iCloud 397
8.9. Storing Files Securely in the App Sandbox 399
8.10. Securing Your User Interface 403
9. Core Location, iBeacon, and Maps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
9.1. Detecting Which Floor the User Is on in a Building 407
9.2. Defining and Processing iBeacons 409
9.3. Pinpointing the Location of a Device 415
9.4. Displaying Pins on a Map View 420
9.5. Displaying Custom Pins on a Map View 423
9.6. Searching on a Map View 429
9.7. Displaying Directions on the Map 434
9.8. Customizing the View of the Map with a Camera 440
10. Gesture Recognizers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445
10.1. Detecting Swipe Gestures 447
10.2. Detecting Rotation Gestures 449
10.3. Detecting Panning and Dragging Gestures 452
10.4. Detecting Long Press Gestures 455
Table of Contents | v
10.5. Detecting Tap Gestures 458
10.6. Detecting Pinch Gestures 460
10.7. Detecting Screen Edge Pan Gestures 462
11. Networking and Sharing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465
11.1. Downloading Data Using NSURLSession 465
11.2. Downloading Data in the Background Using NSURLSession 473
11.3. Uploading Data Using NSURLSession 477
11.4. Downloading Asynchronously with NSURLConnection 479
11.5. Handling Timeouts in Asynchronous Connections 483
11.6. Downloading Synchronously with NSURLConnection 484
11.7. Customizing URL Requests 487
11.8. Sending HTTP Requests with NSURLConnection 488
11.9. Serializing and Deserializing JSON Objects 491
11.10. Integrating Social Sharing into Your Apps 495
12. Multimedia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
12.1. Playing Audio Files 499
12.2. Recording Audio 501
12.3. Playing Video Files 509
12.4. Capturing Thumbnails from Video Files 513
12.5. Accessing the Music Library 516
13. Address Book. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525
13.1. Retrieving a Person Entity with System UI 527
13.2. Retrieving a Property of a Person Entity with System UI 531
13.3. Requesting Access to the Address Book 534
13.4. Retrieving All the People in the Address Book 537
13.5. Retrieving Properties of Address Book Entries 538
13.6. Inserting a Person Entry into the Address Book 541
13.7. Inserting a Group Entry into the Address Book 544
13.8. Adding Persons to Groups 547
13.9. Searching the Address Book 549
13.10. Retrieving and Setting a Person’s Address Book Image 552
14. Files and Folder Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 555
14.1. Finding the Paths of the Most Useful Folders on Disk 557
14.2. Writing to and Reading from Files 559
14.3. Creating Folders on Disk 564
14.4. Enumerating Files and Folders 565
14.5. Deleting Files and Folders 571
14.6. Saving Objects to Files 574
vi | Table of Contents
15. Camera and the Photo Library. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577
15.1. Detecting and Probing the Camera 579
15.2. Taking Photos with the Camera 583
15.3. Taking Videos with the Camera 587
15.4. Storing Photos in the Photo Library 590
15.5. Storing Videos in the Photo Library 595
15.6. Searching for and Retrieving Images and Videos 597
15.7. Reacting to Changes in Images and Videos 602
15.8. Editing Images and Videos Right on the Device 608
16. Notifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 615
16.1. Sending Notifications 616
16.2. Listening for and Reacting to Notifications 618
16.3. Listening and Reacting to Keyboard Notifications 621
16.4. Scheduling Local Notifications 630
16.5. Listening for and Reacting to Local Notifications 636
16.6. Handling Local System Notifications 639
16.7. Setting Up Your App for Push Notifications 642
16.8. Delivering Push Notifications to Your App 648
16.9. Reacting to Push Notifications 656
17. Core Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 659
17.1. Performing Batch Updates on Core Data 661
17.2. Writing to Core Data 664
17.3. Reading Data from Core Data 666
17.4. Deleting Data from Core Data 668
17.5. Sorting Data in Core Data 670
17.6. Boosting Data Access in Table Views 672
17.7. Implementing Relationships in Core Data 680
17.8. Fetching Data in the Background 686
17.9. Using Custom Data Types in Your Core Data Model 690
18. Dates, Calendars, and Events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 697
18.1. Constructing Date Objects 698
18.2. Retrieving Date Components 699
18.3. Requesting Permission to Access Calendars 700
18.4. Retrieving Calendar Groups on an iOS Device 705
18.5. Adding Events to Calendars 707
18.6. Accessing the Contents of Calendars 712
18.7. Removing Events from Calendars 714
18.8. Adding Recurring Events to Calendars 718
18.9. Retrieving the Attendees of an Event 722
Table of Contents | vii
18.10. Adding Alarms to Calendars 725
19. Graphics and Animations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 729
19.1. Drawing Text 734
19.2. Drawing Images 736
19.3. Constructing Resizable Images 739
19.4. Drawing Lines 745
19.5. Constructing Paths 751
19.6. Drawing Rectangles 755
19.7. Adding Shadows to Shapes 759
19.8. Drawing Gradients 764
19.9. Transforming Views 770
19.10. Animating Views 776
20. Core Motion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 787
20.1. Retrieving Altitude Data 788
20.2. Retrieving Pedometer Data 790
20.3. Detecting the Availability of an Accelerometer 794
20.4. Detecting the Availability of a Gyroscope 796
20.5. Retrieving Accelerometer Data 797
20.6. Detecting Shakes on an iOS Device 801
20.7. Retrieving Gyroscope Data 802
21. Cloud. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 805
21.1. Setting Up Your App for CloudKit 807
21.2. Storing Data with CloudKit 812
21.3. Retrieving Data with CloudKit 820
21.4. Querying the Cloud with CloudKit 826
21.5. Observing Changes to Records in CloudKit 831
21.6. Retrieving User Information from CloudKit 839
21.7. Storing and Synchronizing Dictionaries in iCloud 846
21.8. Creating and Managing Files and Folders in iCloud 851
21.9. Searching for Files and Folders in iCloud 855
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 863
viii | Table of Contents