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Introduction 1 How to Use This Book 1 Conventions Used in This Book 2 What You Don''t Have to Read 2 Foolish Assumptions 3 How This Book Is Organized 4
Part 1: Getting Started with Java Programming for Android Developers 4
Part 2: Writing Your Own Java Programs 5
Part 3: Working with the Big Picture: Object-Oriented Programming 5
Part 4: Powering Android with Java Code 5
Part 5: The
Part of Tens 5 More on the web! 6 Icons Used in This Book 6 Beyond the Book 7 Where to Go from Here 7
Part 1: Getting Started with Java Programming For Android Developers 9
Chapter 1: All about Java and Android 11 The Consumer Perspective 12 The Many Faces of Android 13 The Developer Perspective 15 Java 15 Xml 18 Linux 19 From Development to Execution with Java 20 What is a compiler? 20 What is a virtual machine? 24 Java, Android, and Horticulture 26
Chapter 2: Getting the Tools That You Need 27 The Stuff You Need 28 If You Don''t Like to Read the Instructions
. 29 Getting This Book''s Sample Programs 32 Setting Up Java 33 Setting Up Android Studio and the Android SDK 37 Launching the Android Studio IDE 38 Opening One of This Book''s Sample Programs 40 Using Android Studio 42 Starting up 42 The main window 43 Things You Might Eventually Have to Do 48 Installing new versions (and older versions) of Android 49 Creating an Android virtual device 50
Chapter 3: Creating and Running an Android App 55 Creating Your First App 56 First things first 57 Launching your first app 61 If the Emulator Doesn''t Behave 63 Running third-party emulators 64 Testing apps on a physical device 65 The Project Tool Window 68 The app/manifests branch 68 The app/java branch 69 The app/res branches 69 The Gradle scripts branch 70 Dragging, Dropping, and Otherwise Tweaking an App 70 Creating the "look" 71 Coding the behavior 83 What All That Java Code Does 88 Finding the EditText and TextView components 88 Responding to a button click 90 The rest of the code 91 Going Pro 93
Part 2: Writing Your Own Java Programs 95
Chapter 4: An Ode to Code 97 Hello, Android! 97 The Java Class 99 The names of classes 103 Why Java Methods Are Like Meals at a Restaurant 105 What does Mom''s Restaurant have to do with Java? 106 Method declaration 106 Method call 108 Method parameters 108 The chicken or the egg 109 How many parameters? 109 Method declarations and method calls in an Android program 111 Punctuating Your Code 116 Comments are your friends 119 What''s Barry''s excuse? 122 All About Android Activities 123 Extending a class 124 Overriding methods 124 An activity''s workhorse methods 125
Chapter 5: Java''s Building Blocks 129 Info Is As Info Does 130 Variable names 133 Type names 133 Assignments and initializations 134 Expressions and literals 136 How to string characters together 139 Java''s primitive types 140 Things You Can Do with Types 142 Add letters to numbers (Huh?) 144 Java''s exotic assignment operators 146 True bit 147 Java isn''t like a game of horseshoes 148 Use Java''s logical operators 150 Parenthetically speaking 155
Chapter 6: Working with Java Types 157 Working with Strings 157 Going from primitive types to strings 158 Going from strings to primitive types 159 Getting input from the user 160 Practice Safe Typing 163 Widening is good; narrowing is bad 165 Incompatible types 166 Using a hammer to bang a peg into a hole 167
Chapter 7: Though These Be Methods, Yet There Is Madness in''t 169 Minding Your Types When You Call a Method 170 Method parameters and Java types 173 If at first you don''t succeed 174 Return types 174 The great void 175 Displaying numbers 176 Primitive Types and Pass-by Value 177 What''s a developer to do? 181 A final word 183
Chapter 8: What Java Does (and When) 187 Making Decisions 187 Java if statements 189 Choosing among many alternatives 191 Some formalities concerning Java switch statements 198 Repeating Instructions Over and Over Again 199 Check, and then repeat 200 Repeat, and then check 207 Count, count, count 211 What''s Next? 214
Part 3: Working with the Big Picture: Object-oriented Programming 215
Chapter 9: Why Object-Oriented Programming Is Like Selling Cheese 217 Classes and Objects 219 What is a class, really? 220 What is an object? 222 Creating objects 223 Reusing names 227 Calling a constructor 230 More About Classes and Objects (Adding Methods to the Mix) 232 Constructors with parameters 235 The default constructor 239 This is it! 240 Giving an object more responsibility 242 Members of a class 245 Reference types 246 Pass by reference 247 Java''s Modifiers 251 Public classes and default-access classes 251 Access for fields and methods 253 Using getters and setters 257 What does static mean? 260 To dot, or not 263 A bad example 264 What''s Next? 265
Chapter 10: Saving Time and Money: Reusing Existing Code 267 The Last Word on Employees -- Or Is It? 268 Extending a class 269 Overriding methods 272 Java''s super keyword 278 Java annotations 279 More about Java''s Modifiers 281 Keeping Things Simple 285 Using an interface 286 Some Observations about Android''s Classes 291 Java''s super keyword, revisited 292 Casting, again 293
Part 4: Powering Android with Java Code 295
Chapter 11: The Inside Story 297 A Button-Click Example 297 This is a callback 302 Android string resources (A slight detour) 302 Introducing Inner Classes 307 No Publicity, Please! 309 Lambda Expressions 313
Chapter 12: Dealing with a Bunch of Things at a Time 317 Creating a Collection Class 318 More casting 320 Java generics 321 Java''s wrapper classes 325 Stepping Through a Collection 326 Using an iterator 326 The enhanced for statement 328 A cautionary tale 329 Functional programming techniques 331 Java''s Many Collection Classes 332 Arrays 333 String resource arrays 336 Java''s varargs 337 Using Collections in an Android App 340 The listener 343 The adapter 343
Chapter 13: An Android Social Media App 345 The Twitter App''s Files 346 The Twitter4J API jar file 346 The manifest file 348 The main activity''s layout file 349 How to Talk to the Twitter Server 352 Using OAuth 353 Making a ConfigurationBuilder 353 Getting OAuth keys and tokens 355 The Application''s Main Activity 357 The onCreate method 362 The button listener methods 363 The trouble with threads 363 Understanding Android''s AsyncTask 366 My Twitter app''s AsyncTask classes 368 Cutting to the chase, at last 370 Java''s Exceptions 372 Catch clauses 374 A finally clause 375 Passing the buck 376
Chapter 14: Hungry Burds: A Simple Android Game 381 Introducing the Hungry Burds Game 382 The Main Activity 385 The code, all the code, and nothing but the code 388 Measuring the display 392 Constructing a Burd 395 Android animation 398 Creating menus 400 Shared preferences 403 Informing the user 404 It''s Been Fun 405
Part 5: the
Part of Tens 407
Chapter 15: Ten Ways to Avoid Mistakes 409 Putting Capital Letters Where They Belong 409 Breaking Out of a switch Statement 410 Comparing Values with a Double Equal Sign 410 Adding Listeners to Handle Events 411 Defining the Required Constructors 411 Fixing Nonstatic References 412 Staying within Bounds in an Array 412 Anticipating Null Pointers 412 Using Permissions 414 The Activity Not Found 414
Chapter 16: Ten Websites for Developers 415 This Book''s Websites 415 The Horse''s Mouth 416 Finding News and Reviews 416 Index 417