- Accessing Basic Device Information
- Adding Device Capability Restrictions
- Recipe: Checking Device Proximity and Battery States
- Recipe: Recovering Additional Device Information
- Recipe: Using Acceleration to Locate "Up"
- Working with Basic Orientation
- Retrieving the Current Accelerometer Angle Synchronously
- Recipe: Using Acceleration to Move Onscreen Objects
- Recipe: Accelerometer-Based Scroll View
- Recipe: Core Motion Basics
- Recipe: Retrieving and Using Device Attitude
- Detecting Shakes Using Motion Events
- Recipe: Using External Screens
- Tracking Users
- One More Thing: Checking for Available Disk Space
- Summary
Summary
This chapter introduced core ways to interact with an iPhone device. You saw how to recover device info, check the battery state, and subscribe to proximity events. You learned how to differentiate the iPod touch from the iPhone and iPad and determine which model you’re working with. You discovered the accelerometer and saw it in use through several examples, from the simple “finding up” to the more complex shake detection algorithm. You jumped into Core Motion and learned how to create update blocks to respond to device events in real time. Finally, you saw how to add external screen support to your applications. Here are a few parting thoughts about the recipes you just encountered:
- The iPhone’s accelerometer provides a novel way to complement its touch-based interface. Use acceleration data to expand user interactions beyond the “touch here” basics and to introduce tilt-aware feedback.
- Low-level calls can be App Store-friendly. They don’t depend on Apple APIs that may change based on the current firmware release. UNIX system calls may seem daunting, but many are fully supported by the iOS device family.
- Remember device limitations. You may want to check for free disk space before performing file-intensive work and for battery charge before running the CPU at full steam.
- Dive into Core Motion. The real-time device feedback it provides is the foundation for integrating iOS devices into real-world experiences.
- Now that AirPlay has cut the cord for external display tethering, you can use Video Out for many more exciting projects than you might have previously imagined. AirPlay and external video screens mean you can transform your iOS device into a remote control for games and utilities that display on big screens and are controlled on small ones.
- When submitting to iTunes, use your Info.plist file to determine which device capabilities are required. iTunes uses this list of required capabilities to determine whether an application can be downloaded to a given device and run properly on that device.