Objective-C Fundamentals

Front cover......Page 1
contents......Page 8
preface......Page 16
acknowledgments......Page 17
The audience......Page 19
Roadmap......Page 20
Software requirements......Page 21
author online......Page 22
about the cover illustration......Page 23
Part 1—Getting started with Objective-C......Page 24
Building your first iOS application......Page 26
1.1.1 Adapting the Cocoa frameworks for mobile devices......Page 27
1.2 Adjusting your expectations......Page 28
1.2.1 A survey of hardware specifications, circa mid-2011......Page 29
1.3 Using Xcode to develop a simple Coin Toss game......Page 30
1.3.2 Launching Xcode easily......Page 31
1.3.3 Creating the project......Page 32
1.3.4 Writing the source code......Page 35
1.4.1 Adding controls to a view......Page 38
1.4.2 Connecting controls to source code......Page 40
1.6 Taking Coin Toss for a test run......Page 44
1.6.1 Selecting a destination......Page 45
1.6.2 Using breakpoints to inspect the state of a running application......Page 46
1.6.3 Running the CoinToss game in the iPhone simulator......Page 47
1.6.4 Controlling the debugger......Page 48
1.7 Summary......Page 50
Data types, variables, and constants......Page 51
2.1.1 Laying the foundations......Page 52
2.2.1 Counting on your fingers—integral numbers......Page 55
2.2.2 Filling in the gaps—floating-point numbers......Page 58
2.2.3 Characters and strings......Page 60
2.2.4 Boolean truths......Page 62
2.3.1 NSLog and Format Specifiers......Page 63
2.3.2 Type casts and type conversions......Page 66
2.4.1 Enumerations......Page 67
2.4.2 Structures......Page 69
2.4.3 Arrays......Page 71
2.4.4 The importance of descriptive names......Page 73
2.5 Completing Rental Manager v1.0, App Store here we come!......Page 75
2.6 Summary......Page 77
An introduction to objects......Page 78
3.1.2 What are objects?......Page 79
3.1.4 Inheritance and polymorphism......Page 80
3.2 The missing data type: id......Page 81
3.3.2 Obtaining the address of a variable......Page 82
3.3.3 Following a pointer......Page 83
3.3.4 Comparing the values of pointers......Page 84
3.4.1 Sending a message to an object......Page 85
3.4.2 Sending a message to a class......Page 86
3.4.3 Sending nonexistent messages......Page 87
3.4.4 Sending messages to nil......Page 88
3.5.1 Constructing strings......Page 89
3.5.2 Extracting characters from strings......Page 90
3.5.3 Modifying strings......Page 91
3.6 Sample application......Page 92
3.7 Summary......Page 95
Storing data in collections......Page 97
4.1.1 Constructing an array......Page 98
4.1.2 Accessing array elements......Page 99
4.1.3 Searching for array elements......Page 100
4.1.4 Iterating through arrays......Page 102
4.1.5 Adding items to an array......Page 103
4.2.1 Constructing a dictionary......Page 105
4.2.2 Accessing dictionary entries......Page 107
4.2.3 Adding key/value pairs......Page 108
4.2.4 Enumerating all keys and values......Page 109
4.3 Boxing......Page 111
4.3.1 The NSNumber class......Page 112
4.3.3 nil vs. NULL vs. NSNull......Page 113
4.4 Making the Rental Manager application data driven......Page 114
4.5 Summary......Page 117
Part 2—Building your own objects......Page 118
Creating classes......Page 120
5.1.1 Adding a new class to the project......Page 121
5.2 Declaring the interface of a class......Page 122
5.2.1 Instance variables (ivars)......Page 123
5.2.2 Method declarations......Page 124
5.2.3 Fleshing out the header file for the CTRentalProperty class......Page 128
5.3.2 Accessing instance variables......Page 129
5.3.3 Sending messages to self......Page 130
5.3.4 Fleshing out the method file for the CTRentalProperty class......Page 131
5.4.1 @property syntax......Page 132
5.4.2 Synthesizing property getters and setters......Page 135
5.4.3 Dot syntax......Page 136
5.5.1 Creating and initializing objects......Page 138
5.5.2 init is pretty dumb......Page 139
5.5.3 Combining allocation and initialization......Page 141
5.5.4 Destroying objects......Page 142
5.6 Using the class in the Rental Manager application......Page 143
5.7 Summary......Page 146
6.1 Subclassing......Page 147
6.1.1 What is subclassing?......Page 148
6.2 Adding new instance variables......Page 150
6.3 Accessing existing instance variables......Page 152
6.3.1 Manual getters and setters approach......Page 153
6.4 Overriding methods......Page 154
6.4.1 Overriding the description method......Page 155
6.5.1 Why use class clusters......Page 157
6.5.2 Multiple public clusters......Page 158
6.6.2 Using a category......Page 159
6.7 Subclassing in your demo application......Page 161
6.7.1 Creating and subclassing CTLease......Page 162
6.7.2 Creating CTPeriodicLease as a subclass of CTLease......Page 163
6.7.3 Creating CTFixedLease as a subclass of CTLease......Page 164
6.8 Summary......Page 166
Protocols......Page 167
7.1 Defining a protocol......Page 168
7.2 Implementing a protocol......Page 169
7.2.1 Creating the protocol method callers......Page 170
7.2.2 Making a class conform to a protocol......Page 171
7.3.1 ......Page 173
7.3.2 ......Page 176
7.3.3 ......Page 180
7.3.4 NSXMLParser......Page 181
7.4 Summary......Page 185
Dynamic typing and runtime type information......Page 186
8.1.1 Making assumptions about the runtime type......Page 187
8.3 How messaging works......Page 189
8.3.1 Methods, selectors, and implementations......Page 190
8.3.2 Handling unknown selectors......Page 192
8.3.3 Sending a message to nil......Page 193
8.4.2 Sending a message generated at runtime......Page 194
8.4.3 Adding new methods to a class at runtime......Page 196
8.5 Practical uses of runtime type introspection......Page 197
8.6 Summary......Page 199
Memory management......Page 200
9.1 Object ownership......Page 201
9.2 Reference counting......Page 202
9.2.1 Releasing an object......Page 203
9.2.2 Retaining an object......Page 204
9.2.3 Determining the current retain count......Page 205
9.3 Autorelease pools......Page 207
9.3.3 Creating a new autorelease pool......Page 208
9.3.5 Why not use an autorelease pool for everything?......Page 210
9.4 Memory zones......Page 213
9.5 Rules for object ownership......Page 215
9.6.1 Implementing the UIApplicationDelegate protocol......Page 216
9.6.2 Overriding didReceiveMemoryWarning......Page 217
9.6.3 Observing the UIApplicationDidReceiveMemoryWarningNotification......Page 220
9.7 Summary......Page 222
Part 3—Making maximum use of framework functionality......Page 224
Error and exception handling......Page 226
10.1.1 Getting NSError to talk......Page 227
10.1.2 Examining NSError’s userInfo Dictionary......Page 228
10.2.1 Introducing RentalManagerAPI......Page 229
10.2.2 Handling and displaying RentalManagerAPI errors......Page 232
10.3.1 Throwing exceptions......Page 233
10.4 Summary......Page 234
Key-Value Coding and NSPredicate......Page 235
11.1 Making your objects KVC-compliant......Page 236
11.1.1 Accessing properties via KVC......Page 237
11.1.3 Returning multiple values......Page 238
11.1.4 Aggregating and collating values......Page 239
11.2.1 Handling unknown keys......Page 240
11.2.2 Handling nil values......Page 241
11.3.1 Evaluating a predicate......Page 242
11.3.3 Expressing your predicate condition......Page 243
11.3.4 More complex conditions......Page 244
11.3.5 Using key paths in predicate expressions......Page 245
11.3.6 Parameterizing and templating predicate expressions......Page 246
11.4 Sample application......Page 247
11.5 Summary......Page 250
Reading and writing application data......Page 251
12.1.1 What does Core Data do?......Page 252
12.2.2 Persistent store coordinator......Page 254
12.3.1 Core Data entities......Page 255
12.3.2 Core Data attributes......Page 256
12.4.1 Examining the Xcode Core Data template......Page 257
12.4.2 Building the data model......Page 258
12.4.3 Defining the relationships......Page 259
12.4.4 Creating Person entities in pure code......Page 260
12.4.5 Fetching Person entities in pure code......Page 262
12.4.6 Adding a master TableView......Page 263
12.4.7 Adding and deleting people......Page 266
12.4.8 Managing tasks......Page 269
12.4.9 Using model objects......Page 272
12.5.1 Changing the data model......Page 274
12.5.3 Error handling and validation......Page 276
12.6 Summary......Page 279
Blocks and Grand Central Dispatch......Page 280
13.1 The syntax of blocks......Page 281
13.1.1 Blocks are closures......Page 283
13.1.2 Blocks and memory management......Page 285
13.1.3 Block-based APIs in Apple’s iOS frameworks......Page 287
13.2 Performing work asynchronously......Page 288
13.2.2 GCD fundamentals......Page 289
13.2.3 Building RealEstateViewer......Page 290
13.2.4 Making the image search asynchronous......Page 294
13.2.5 Making the image loading asynchronous......Page 296
13.3 Summary......Page 297
Debugging techniques......Page 299
14.1 Building an application, complete with bugs......Page 300
14.2 Understanding NSLog......Page 301
14.3 Bringing memory leaks under control with Instruments......Page 304
14.4 Detecting zombies......Page 307
14.5 Summary......Page 309
A.1.2 System requirements......Page 311
A.2.1 Creating a certificate......Page 312
A.2.2 Provisioning a device using Xcode......Page 313
A.2.3 Provisioning a device manually......Page 314
A.2.4 Running an application on a device......Page 315
B.1 Variable naming conventions......Page 316
B.1.1 Hungarian notation......Page 317
B.1.3 Namespaces......Page 318
B.2.2 Comparison operators......Page 319
B.2.3 Bitwise operators......Page 321
B.2.4 Assignment operators......Page 322
B.3 Conditional statements......Page 323
B.3.1 The if-else statement......Page 324
B.3.2 The conditional operator......Page 325
B.3.3 The switch statement......Page 326
B.4 Looping statements......Page 328
B.4.1 The while statement......Page 329
B.4.2 The do-while statement......Page 330
B.4.3 The for statement......Page 331
B.4.4 Controlling loops......Page 332
B.5 Summary......Page 334
C.1 A short history of Objective-C......Page 335
C.1.2 Popularization via NeXT Inc.......Page 336
C.1.3 Adoption and evolution by Apple Inc.......Page 337
C.3 The iPhone SDK: Safari......Page 338
C.3.1 HTML5, CSS3, and other modern standards......Page 339
C.3.2 iPhone OS integration......Page 340
C.3.3 PhoneGap and other extensible cross-platform solutions......Page 342
C.4 Scripting languages: Lua and Ruby......Page 343
C.5 The 10,000-pound gorilla in the room: Adobe Flash......Page 345
C.6 Mono (.NET)......Page 346
C.7 Summary......Page 348
Symbols......Page 350
A......Page 351
C......Page 352
D......Page 354
G......Page 356
I......Page 357
L......Page 358
M......Page 359
N......Page 360
O......Page 361
P......Page 362
S......Page 363
T......Page 364
V......Page 365
Z......Page 366
Back cover......Page 368