Table Of ContentiOS 7 Programming Cookbook
Vandad Nahavandipoor
iOS 7 Programming Cookbook
by Vandad Nahavandipoor
Copyright © 2014 Vandad Nahavandipoor. All rights reserved.
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October 2013: First Edition
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2013-10-09: First release
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ISBN: 978-1-449-37242-2
[QG]
Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
1. Implementing Controllers and Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1. Displaying Alerts with UIAlertView 23
1.2. Creating and Using Switches with UISwitch 32
1.3. Customizing the UISwitch 36
1.4. Picking Values with the UIPickerView 39
1.5. Picking the Date and Time with UIDatePicker 45
1.6. Implementing Range Pickers with UISlider 50
1.7. Customizing the UISlider 54
1.8. Grouping Compact Options with UISegmentedControl 59
1.9. Presenting and Managing Views with UIViewController 63
1.10. Presenting Sharing Options with UIActivityViewController 67
1.11. Presenting Custom Sharing Options with UIActivityViewController 73
1.12. Implementing Navigation with UINavigationController 79
1.13. Manipulating a Navigation Controller’s Array of View Controllers 85
1.14. Displaying an Image on a Navigation Bar 86
1.15. Adding Buttons to Navigation Bars Using UIBarButtonItem 88
1.16. Presenting Multiple View Controllers with UITabBarController 94
1.17. Displaying Static Text with UILabel 101
1.18. Customizing the UILabel 105
1.19. Accepting User Text Input with UITextField 108
1.20. Displaying Long Lines of Text with UITextView 118
1.21. Adding Buttons to the User Interface with UIButton 123
1.22. Displaying Images with UIImageView 127
1.23. Creating Scrollable Content with UIScrollView 132
1.24. Loading Web Pages with UIWebView 137
1.25. Displaying Progress with UIProgressView 141
1.26. Constructing and Displaying Styled Texts 143
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1.27. Presenting Master-Detail Views with UISplitViewController 148
1.28. Enabling Paging with UIPageViewController 153
1.29. Displaying Popovers with UIPopoverController 158
2. Creating Dynamic and Interactive User Interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
2.1. Adding Gravity to Your UI Components 171
2.2. Detecting and Reacting to Collisions Between UI Components 172
2.3. Animating Your UI Components with a Push 180
2.4. Attaching Multiple Dynamic Items to Each Other 184
2.5. Adding a Dynamic Snap Effect to Your UI Components 189
2.6. Assigning Characteristics to Your Dynamic Effects 192
3. Auto Layout and the Visual Format Language. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
3.1. Placing UI Components in the Center of the Screen 201
3.2. Defining Horizontal and Vertical Constraints with the Visual Format
Language 203
3.3. Utilizing Cross View Constraints 210
3.4. Configuring Auto Layout Constraints in Interface Builder 217
4. Constructing and Using Table Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
4.1. Populating a Table View with Data 225
4.2. Using Different Types of Accessories in a Table View Cell 229
4.3. Creating Custom Table View Cell Accessories 232
4.4. Enabling Swipe Deletion of Table View Cells 235
4.5. Constructing Headers and Footers in Table Views 237
4.6. Displaying Context Menus on Table View Cells 246
4.7. Moving Cells and Sections in Table Views 251
4.8. Deleting Cells and Sections from Table Views 257
4.9. Utilizing the UITableViewController for Easy Creation of Table Views 268
4.10. Displaying a Refresh Control for Table Views 274
5. Building Complex Layouts with Collection Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
5.1. Constructing Collection Views 281
5.2. Assigning a Data Source to a Collection View 284
5.3. Providing a Flow Layout to a Collection View 285
5.4. Providing Basic Content to a Collection View 288
5.5. Feeding Custom Cells to Collection Views Using .xib Files 294
5.6. Handling Events in Collection Views 299
5.7. Providing a Header and a Footer in a Flow Layout 303
5.8. Adding Custom Interactions to Collection Views 308
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5.9. Providing Contextual Menus on Collection View Cells 311
6. Storyboards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
6.1. Adding a Navigation Controller to a Storyboard 316
6.2. Passing Data from One Screen to Another 318
6.3. Adding a Tab Bar Controller to a Storyboard 325
6.4. Introducing Custom Segue Transitions to Your Storyboard 328
6.5. Placing Images and Other UI Components on Storyboards 332
7. Concurrency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
7.1. Constructing Block Objects 342
7.2. Accessing Variables in Block Objects 346
7.3. Invoking Block Objects 352
7.4. Performing UI-Related Tasks with GCD 354
7.5. Executing Non-UI Related Tasks Synchronously with GCD 358
7.6. Executing Non-UI Related Tasks Asynchronously with GCD 361
7.7. Performing Tasks after a Delay with GCD 368
7.8. Performing a Task Only Once with GCD 371
7.9. Grouping Tasks Together with GCD 373
7.10. Constructing Your Own Dispatch Queues with GCD 377
7.11. Running Tasks Synchronously with Operations 380
7.12. Running Tasks Asynchronously with Operations 387
7.13. Creating Dependency Between Operations 393
7.14. Creating Timers 395
7.15. Creating Concurrency with Threads 400
7.16. Invoking Background Methods 406
7.17. Exiting Threads and Timers 407
8. Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
8.1. Enabling Security and Protection for Your Apps 418
8.2. Storing Values in the Keychain 422
8.3. Finding Values in the Keychain 424
8.4. Updating Existing Values in the Keychain 429
8.5. Deleting Exiting Values in the Keychain 432
8.6. Sharing Keychain Data Between Multiple Apps 434
8.7. Writing to and Reading Keychain Data from iCloud 440
8.8. Storing Files Securely in the App Sandbox 443
8.9. Securing Your User Interface 446
9. Core Location and Maps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449
9.1. Creating a Map View 450
9.2. Handling the Events of a Map View 452
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9.3. Pinpointing the Location of a Device 453
9.4. Displaying Pins on a Map View 455
9.5. Displaying Pins with Different Colors on a Map View 459
9.6. Displaying Custom Pins on a Map View 465
9.7. Converting Meaningful Addresses to Longitude and Latitude 468
9.8. Converting Longitude and Latitude to a Meaningful Address 470
9.9. Searching on a Map View 472
9.10. Displaying Directions on the Map 475
10. Implementing Gesture Recognizers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 481
10.1. Detecting Swipe Gestures 483
10.2. Detecting Rotation Gestures 485
10.3. Detecting Panning and Dragging Gestures 489
10.4. Detecting Long-Press Gestures 491
10.5. Detecting Tap Gestures 495
10.6. Detecting Pinch Gestures 497
11. Networking, JSON, XML, and Sharing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501
11.1. Downloading Asynchronously with NSURLConnection 501
11.2. Handling Timeouts in Asynchronous Connections 504
11.3. Downloading Synchronously with NSURLConnection 506
11.4. Modifying a URL Request with NSMutableURLRequest 508
11.5. Sending HTTP GET Requests with NSURLConnection 509
11.6. Sending HTTP POST Requests with NSURLConnection 511
11.7. Sending HTTP DELETE Requests with NSURLConnection 513
11.8. Sending HTTP PUT Requests with NSURLConnection 514
11.9. Serializing Arrays and Dictionaries into JSON 516
11.10. Deserializing JSON into Arrays and Dictionaries 518
11.11. Integrating Social Sharing into Your Apps 521
11.12. Parsing XML with NSXMLParser 525
12. Audio and Video. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 531
12.1. Playing Audio Files 531
12.2. Handling Interruptions While Playing Audio 534
12.3. Recording Audio 535
12.4. Handling Interruptions While Recording Audio 542
12.5. Playing Audio over Other Active Sounds 543
12.6. Playing Video Files 547
12.7. Capturing Thumbnails from Video Files 551
12.8. Accessing the Music Library 554
13. Address Book. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 563
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13.1. Requesting Access to the Address Book 564
13.2. Retrieving a Reference to an Address Book 568
13.3. Retrieving All the People in the Address Book 571
13.4. Retrieving Properties of Address Book Entries 573
13.5. Inserting a Person Entry into the Address Book 577
13.6. Inserting a Group Entry into the Address Book 581
13.7. Adding Persons to Groups 584
13.8. Searching the Address Book 587
13.9. Retrieving and Setting a Person’s Address Book Image 592
14. Files and Folder Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
14.1. Finding the Paths of the Most Useful Folders on Disk 603
14.2. Writing to and Reading from Files 605
14.3. Creating Folders on Disk 610
14.4. Enumerating Files and Folders 612
14.5. Deleting Files and Folders 618
14.6. Saving Objects to Files 621
15. Camera and the Photo Library. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
15.1. Detecting and Probing the Camera 627
15.2. Taking Photos with the Camera 632
15.3. Taking Videos with the Camera 636
15.4. Storing Photos in the Photo Library 639
15.5. Storing Videos in the Photo Library 644
15.6. Retrieving Photos and Videos from the Photo Library 646
15.7. Retrieving Assets from the Assets Library 649
15.8. Editing Videos on an iOS Device 656
16. Multitasking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 663
16.1. Detecting the Availability of Multitasking 664
16.2. Completing a Long-Running Task in the Background 665
16.3. Adding Background Fetch Capabilities to Your Apps 669
16.4. Playing Audio in the Background 678
16.5. Handling Location Changes in the Background 682
16.6. Saving and Loading the State of Multitasking Apps 684
16.7. Handling Network Connections in the Background 688
16.8. Opting Out of Multitasking 691
17. Notifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 693
17.1. Sending Notifications 694
17.2. Listening for and Reacting to Notifications 696
17.3. Listening and Reacting to Keyboard Notifications 700
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17.4. Scheduling Local Notifications 707
17.5. Listening for and Reacting to Local Notifications 711
17.6. Handling Local System Notifications 714
17.7. Setting Up Your App for Push Notifications 718
17.8. Delivering Push Notifications to Your App 724
17.9. Reacting to Push Notifications 732
18. Core Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735
18.1. Creating a Core Data Model with Xcode 737
18.2. Generating Class Files for Core Data Entities 741
18.3. Creating and Saving Data Using Core Data 745
18.4. Reading Data from Core Data 747
18.5. Deleting Data from Core Data 750
18.6. Sorting Data in Core Data 752
18.7. Boosting Data Access in Table Views 754
18.8. Implementing Relationships in Core Data 761
18.9. Fetching Data in the Background 768
18.10. Using Custom Data Types in Your Core Data Model 772
19. Dates, Calendars, and Events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 779
19.1. Requesting Permission to Access Calendars 784
19.2. Retrieving Calendar Groups on an iOS Device 790
19.3. Adding Events to Calendars 792
19.4. Accessing the Contents of Calendars 796
19.5. Removing Events from Calendars 799
19.6. Adding Recurring Events to Calendars 803
19.7. Retrieving the Attendees of an Event 808
19.8. Adding Alarms to Calendars 811
19.9. Handling Event Changed Notifications 814
19.10. Presenting Event View Controllers 816
19.11. Presenting Event Edit View Controllers 822
20. Graphics and Animations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 827
20.1. Enumerating and Loading Fonts 833
20.2. Drawing Text 835
20.3. Constructing, Setting, and Using Colors 836
20.4. Drawing Images 841
20.5. Constructing Resizable Images 845
20.6. Drawing Lines 850
20.7. Constructing Paths 858
20.8. Drawing Rectangles 862
20.9. Adding Shadows to Shapes 866
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