programming ios 7, 4th edition

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Matt Neuburg

FOURTH EDITION

Programming iOS 7

www.it-ebooks.info

Programming iOS 7, Fourth Edition

by Matt Neuburg

Copyright © 2014 Matt Neuburg. All rights reserved.

Printed in the United States of America.

Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472.

O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions are

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Editor: Rachel Roumeliotis

Production Editor: Kristen Brown

Proofreader: O’Reilly Production Services

Indexer: Matt Neuburg

Cover Designer: Randy Comer

Interior Designer: David Futato

Illustrator: Matt Neuburg

May 2011: First Edition

March 2012: Second Edition

March 2013: Third Edition

December 2013: Fourth Edition

Revision History for the Fourth Edition:

2013-12-09: First release

See http://oreilly.com/catalog/errata.csp?isbn=9781449372347 for release details.

Nutshell Handbook, the Nutshell Handbook logo, and the O’Reilly logo are registered trademarks of O’Reilly

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While every precaution has been taken in the preparation of this book, the publisher and author assume no

responsibility for errors or omissions, or for damages resulting from the use of the information contained

herein.

ISBN: 978-1-449-37234-7

[LSI]

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Table of Contents

Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv

Part I. Views

1. Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

The Window 4

Experimenting With Views 7

Subview and Superview 8

Visibility and Opacity 11

Frame 12

Bounds and Center 13

Transform 16

Layout 22

Autoresizing 23

Autolayout 27

Constraints in the Nib 38

Order of Layout Events 45

Autolayout and View Transforms 46

2. Drawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

UIImage and UIImageView 49

Resizable Images 53

Image Rendering Mode 56

Graphics Contexts 58

UIImage Drawing 61

CGImage Drawing 63

Snapshots 66

CIFilter and CIImage 68

Drawing a UIView 72

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Graphics Context Settings 74

Paths and Shapes 75

Clipping 79

Gradients 80

Colors and Patterns 82

Graphics Context Transforms 84

Shadows 86

Erasing 87

Points and Pixels 88

Content Mode 89

3. Layers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

View and Layer 92

Layers and Sublayers 94

Manipulating the Layer Hierarchy 97

Positioning a Sublayer 98

CAScrollLayer 99

Layout of Sublayers 99

Drawing in a Layer 100

Content Resizing and Positioning 104

Layers that Draw Themselves 106

Transforms 108

Depth 111

Shadows, Borders, and Masks 115

Layer Efficiency 116

Layers and Key–Value Coding 118

4. Animation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

Drawing, Animation, and Threading 122

UIImageView and UIImage Animation 125

View Animation 126

Block-Based View Animation 127

View Animation Options 129

Springing View Animation 134

Keyframe View Animation 134

Transitions 136

Implicit Layer Animation 138

Animation Transactions 140

Media Timing Functions 141

Core Animation 143

CABasicAnimation and Its Inheritance 143

Using a CABasicAnimation 145

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Keyframe Animation 149

Making a Property Animatable 150

Grouped Animations 151

Transitions 155

Animations List 157

Actions 159

What an Action Is 160

Action Search 160

Hooking Into the Action Search 162

Nonproperty Actions 164

Emitter Layers 166

CIFilter Transitions 171

UIKit Dynamics 174

Motion Effects 180

Animation and Autolayout 181

5. Touches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

Touch Events and Views 186

Receiving Touches 187

Restricting Touches 189

Interpreting Touches 190

Gesture Recognizers 195

Gesture Recognizer Classes 195

Gesture Recognizer Conflicts 200

Subclassing Gesture Recognizers 203

Gesture Recognizer Delegate 205

Gesture Recognizers in the Nib 207

Touch Delivery 208

Hit-Testing 208

Initial Touch Event Delivery 214

Gesture Recognizer and View 214

Touch Exclusion Logic 216

Gesture Recognition Logic 216

Touches and the Responder Chain 218

Part II. Interface

6. View Controllers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

View Controller Responsibilities 224

View Controller Hierarchy 225

View Controller Creation 231

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How a View Controller Gets Its View 234

Manual View 235

Generic Automatic View 237

View in a Separate Nib 238

Nib-Instantiated View Controller 241

Storyboard-Instantiated View Controller 243

View Resizing and the Status Bar 245

Rotation 251

Rotation and Layout Events 254

Initial Orientation 258

Presented View Controller 261

Presenting a View 262

Communication With a Presented View Controller 264

Presented View Animation 267

Presentation Styles 268

Rotation of a Presented View 271

Presenting a View in Response to Rotation 273

Tab Bar Controllers 274

Tab Bar Items 276

Configuring a Tab Bar Controller 277

Navigation Controllers 279

Bar Button Items 282

Navigation Items and Toolbar Items 284

Configuring a Navigation Controller 287

Custom Transition Animations 290

Noninteractive Custom Transition Animation 291

Interactive Custom Transition Animation 294

Custom Presented View Controller Transition 301

Transition Coordinator 308

Page View Controller 310

Container View Controllers 315

Storyboards 320

Segues 322

Container Views 324

Unwind Segues 325

View Controller Lifetime Events 329

Incoherencies in View Controller Events 332

Appear and Disappear Events 332

Manual Event Forwarding to a Child View Controller 333

View Controller Memory Management 335

State Restoration 337

How to Test State Restoration 338

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Participating in State Restoration 339

Restoration ID, Identifier Path, and Restoration Class 341

Restoring View Controller State 348

Restoration Order of Operations 353

Restoration of Other Objects 355

Snapshot Suppression 357

7. Scroll Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359

Creating a Scroll View in Code 360

Using a Content View 363

Scroll View in a Nib 365

Scrolling 367

Paging 371

Tiling 373

Zooming 375

Zooming Programmatically 376

Zooming with Detail 377

Scroll View Delegate 380

Scroll View Touches 382

Floating Scroll View Subviews 386

Scroll View Performance 387

8. Table Views and Collection Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389

Table View Cells 392

Built-In Cell Styles 393

Registering a Cell Class 399

Custom Cells 401

Table View Data 408

The Three Big Questions 409

Reusing Cells 411

Table View Sections 413

Section Index 418

Refreshing Table View Data 419

Variable Row Heights 423

Table View Cell Selection 426

Managing Cell Selection 426

Responding to Cell Selection 427

Navigation From a Table View 429

Cell Choice and Static Tables 430

Table View Scrolling and Layout 432

Table View State Restoration 432

Table View Searching 433

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Table View Editing 442

Deleting Table Items 445

Editable Content in Table Items 446

Inserting Table Items 448

Rearranging Table Items 450

Dynamic Table Items 451

Table View Menus 453

Collection Views 455

Collection View Classes 459

Using a Collection View 462

Custom Collection View Layouts 465

Switching Layouts 469

Collection Views and UIKit Dynamics 470

9. Popovers and Split Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473

Preparing a Popover 475

Popover Size 476

Popover Appearance Customization 477

Summoning and Dismissing a Popover 480

Popover Segues 480

Managing a Popover Controller 481

Dismissing a Popover 482

Popovers During Rotation or Backgrounding 485

Popovers and Presented Views 486

Automatic Popovers 487

Split Views 489

Using a Split View 489

Split Views in a Storyboard 491

Other Split View Configurations 492

10. Text. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 493

Fonts 494

Fonts and Dynamic Type 494

Font Descriptors 497

Attributed Strings 499

Attributed String Attributes 500

Making an Attributed String 503

Modifying and Querying an Attributed String 508

Measuring and Drawing an Attributed String 509

Labels 511

Number of Lines 511

Wrapping and Truncation 512

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Label Resizing 513

Customized Label Drawing 514

Text Fields 515

Summoning and Dismissing the Keyboard 517

Keyboard Covers Text Field 519

Configuring the Keyboard 524

Text Field Delegate and Control Event Messages 525

Text Field Menu 528

Text Views 530

Text View as Scroll View 531

Text View and Keyboard 532

Text Kit 534

Text Container 535

Alternative Text Kit Stack Architectures 538

Layout Manager 540

Text Kit Without a Text View 543

11. Web Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 549

Web View Content 550

Loading Web View Content 554

Designing Web View Content 556

Paginated Web Views 558

Web View State Restoration 558

Communicating with a Web View 559

12. Controls and Other Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 563

UIActivityIndicatorView 563

UIProgressView 565

UIPickerView 567

UISearchBar 569

UIControl 574

UISwitch 578

UIStepper 579

UIPageControl 581

UIDatePicker 581

UISlider 584

UISegmentedControl 587

UIButton 590

Custom Controls 595

Bars 598

Bar Position and Bar Metrics 599

Bar Appearance 601

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UIBarButtonItem 602

UINavigationBar 604

UIToolbar 607

UITabBar 607

Tint Color 612

Appearance Proxy 614

13. Modal Dialogs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 619

Alert View 620

Action Sheet 622

Dialog Alternatives 627

Local Notifications 628

Activity View 632

Part III. Some Frameworks

14. Audio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639

System Sounds 639

Audio Session 640

Interruptions 643

Routing Changes 645

Audio Player 646

Remote Control of Your Sound 648

Playing Sound in the Background 651

Further Topics in Sound 654

15. Video. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 657

MPMoviePlayerController 658

MPMoviePlayerViewController 664

UIVideoEditorController 665

Introduction to AV Foundation 668

Some AV Foundation Building Blocks 668

Displaying a Movie 669

Synchronizing Video With Animation 671

Building Media 672

Further Exploration of AV Foundation 673

16. Music Library. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 675

Exploring the Music Library 675

Querying the Music Library 676

Persistence and Change in the Music Library 680

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Music Player 681

MPVolumeView 684

Playing Songs With AV Foundation 686

Music Picker 688

17. Photo Library and Image Capture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 693

Choosing From the Photo Library 693

Assets Library Framework 697

Using the Camera 701

Customizing the Image Capture Interface 703

Image Capture With AV Foundation 705

18. Address Book. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 709

Address Book Database 709

Address Book Interface 714

ABPeoplePickerNavigationController 715

ABPersonViewController 717

ABNewPersonViewController 718

ABUnknownPersonViewController 719

19. Calendar. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 721

Calendar Database 721

Creating Calendars and Events 725

Recurrence 727

Fetching Events 729

Reminders 731

Proximity Alarms 732

Calendar Interface 732

EKEventViewController 733

EKEventEditViewController 735

EKCalendarChooser 736

20. Mail and Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 739

Mail Message 739

Text Message 741

Twitter Post 742

21. Maps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 743

Displaying a Map 743

Annotations 746

Custom Annotation View 747

Custom Annotation Class 751

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Other Annotation Features 752

Overlays 754

Custom Overlay Class 755

Custom Overlay Renderer 758

Other Overlay Features 760

Map Kit and Current Location 761

Communicating With the Maps App 762

Geocoding, Searching, and Directions 764

Geocoding 764

Searching 766

Directions 766

22. Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 769

Core Location 770

Basic Location Determination 771

Heading 775

Background Location 776

Acceleration and Attitude 779

Shake Events 780

Raw Acceleration 781

Gyroscope 785

Part IV. Final Topics

23. Persistent Storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 793

The Sandbox 793

Basic File Operations 794

Saving and Reading Files 796

User Defaults 798

File Sharing 799

Document Types 800

Handing Off a Document 803

Document Architecture 806

iCloud 811

XML 814

SQLite 821

Core Data 821

Image File Formats 827

24. Basic Networking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 831

HTTP Requests 831

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Simple HTTP Request 833

Formal HTTP Request 834

Multiple Tasks 839

Background Downloads 845

Background App Refresh 847

In-App Purchases 848

Bonjour 852

25. Threads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 855

Main Thread 855

Why Threading Is Hard 858

Three Ways of Threading 860

Manual Threads 861

NSOperation 863

Grand Central Dispatch 867

Threads and App Backgrounding 872

26. Undo. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 875

Undo Manager 875

Target–Action Undo 876

Undo Grouping 878

Invocation Undo 879

Undo Interface 880

Shake-To-Edit 880

Undo Menu 881

A. Application Lifetime Events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 883

Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 889

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