You are previewing Learning iPhone Programming.

Learning iPhone Programming

Cover of Learning iPhone Programming by Alasdair Allan Published by O'Reilly Media, Inc.
  1. Learning iPhone Programming
    1. SPECIAL OFFER: Upgrade this ebook with O’Reilly
    2. A Note Regarding Supplemental Files
    3. Preface
      1. Who Should Read This Book?
      2. What Should You Already Know?
      3. What Will You Learn?
      4. What’s in This Book?
      5. Conventions Used in This Book
      6. Using Code Examples
      7. How to Contact Us
      8. Safari® Books Online
      9. Acknowledgments
    4. 1. Why Go Native?
      1. The Pros and Cons
      2. The Release Cycle
      3. Build It and They Will Come
    5. 2. Becoming a Developer
      1. Registering As an iPhone Developer
      2. Enrolling in the iPhone Developer Program
      3. The Apple Developer Connection
      4. Installing the iPhone SDK
      5. Preparing Your iPhone or iPod touch
    6. 3. Your First iPhone App
      1. Objective-C Basics
      2. Creating a Project
    7. 4. Coding in Objective-C
      1. Declaring and Defining Classes
      2. Memory Management
      3. Fundamental iPhone Design Patterns
      4. Conclusion
    8. 5. Table-View-Based Applications
      1. Simplifying the Template Classes
      2. Creating a Table View
      3. Building a Model
      4. Connecting the Controller to the Model
      5. Adding Navigation Controls to the Application
      6. Adding a City View
      7. Edit Mode
    9. 6. Other View Controllers
      1. Utility Applications
      2. Tab Bar Applications
      3. Modal View Controllers
      4. The Image Picker View Controller
    10. 7. Connecting to the Network
      1. Detecting Network Status
      2. Embedding a Web Browser in Your App
      3. Sending Email
      4. Getting Data from the Internet
    11. 8. Handling Data
      1. Data Entry
      2. Parsing XML
      3. Parsing JSON
      4. Regular Expressions
      5. Storing Data
    12. 9. Distributing Your Application
      1. Adding Missing Features
      2. Building and Signing
      3. Submitting to the App Store
      4. Reasons for Rejection
    13. 10. Using Sensors
      1. Hardware Support
      2. Using the Camera
      3. The Core Location Framework
      4. Using the Accelerometer
      5. Using the Digital Compass
      6. Accessing the Proximity Sensor
      7. Using Vibration
    14. 11. Geolocation and Mapping
      1. User Location
      2. Annotating Maps
    15. 12. Integrating Your Application
      1. Application Preferences
      2. Custom URL Schemes
      3. Media Playback
      4. Using the Address Book
    16. 13. Other Native Platforms
      1. PhoneGap
      2. MonoTouch
    17. 14. Going Further
      1. Cocoa and Objective-C
      2. Web Applications
      3. Core Data
      4. Push Notifications
      5. In-App Purchase
      6. Core Animation
      7. Game Kit
      8. Writing Games
      9. Look and Feel
      10. Hardware Accessories
    18. Index
    19. About the Author
    20. Colophon
    21. SPECIAL OFFER: Upgrade this ebook with O’Reilly
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Storing Data

If the user creates data while running your application, you may need a place to store the data so that it’s there the next time the user runs it. You’ll also want to store user preferences, passwords, and many other forms of data. You could store data online somewhere, but then your application won’t function unless it’s online. The iPhone can store data in lots of ways.

Using Flat Files

So-called flat files are files that contain data, but are typically not backed by the power of a full-featured database system. They are useful for storing small bits of text data, but they lack the performance and organizational advantages that a database provides.

Applications running on the iPhone or iPod touch are sandboxed; you can access only a limited subset of the filesystem from your application. If you want to save files from your application, you should save them into the application’s Document directory.

Here’s the code you need to locate the application’s Document directory:

NSArray *arrayPaths = NSSearchPathForDirectoriesInDomains(
  NSDocumentDirectory,   NSUserDomainMask, YES);
NSString *docDirectory = [arrayPaths objectAtIndex:0];1
1

The first entry in the array will contain the file path to the application’s Document directory.

Reading and writing text content

The NSFileManager methods ...

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