IOS

IOS之CorMotion与MapKit

Posted by jjx on October 14, 2016

Application Lifecycle and Core Motion

  • Notification
    • For Model (or global) to Controller communication
    • NSnotificationCenter，类似一个观察者模式，注册并获取变动时的通知
  • Application Lifecycle
    • Not running, Inactive, Active, Background, Suspended
    • application(UIApplication, didFinishLauchingWithOptions: [NSObject: AnyObject])
    • 用来知道自己的 app 是在什么情况下被打开的（不只是用户点击这一种）
  • UIApplication
    • Shared instance
      • manages all global behavior
      • never need to subclass it
      • It delegates everything you need to be involved in to its UIApplicationDelegate
  • Info.plist
    • Many of your application’s settings are in Info.plist
  • Capabilities
    • Some features require enabling (iCloud, Game Center, etc)
    • Switch on in Capabilities tab (Inside your Project Settings)
  • Airdrop 需要先注册，参考 Trak 的 info.plist
  • Core Motion
    • API to access motion sensing hardware on your device
    • Primary inputs: Accelerometer, Gyro, Magnetometer
    • Class used to get this input is CMMotionManager
    • Usage
      • Check to see what hardware is available
      • Start the sampling going and poll the motion manager for the latest sample it have
      • …or…
      • check to see what hardware is available
      • Set the rate at which you want data to be reported from the hardware
      • Register a closure (and a queue to run it on) to call each time a sample is taken
    • Checking availability of hardware sensor
      • var {accelerometer, gyro, magnetometer, deviceMotion}Available: Bool
    • Starting the hardware sensors collecting data
      • you only need to do this if you are going to poll for data
      • func start{Accelerometer, Gyro, Magnetometer, DeviceMotion}Updates()
    • Is the hardware currently collection data?
      • var {accelerometer,gyro,magnetometer,deviceMotion}Active: Bool
    • Stop the hardware collecting data
      • func stop{Accelerometer,Gyro,Magnetometer,DeviceMotion}Updates()
  • CMDeviceMotion
    • 各种传感器的组合

Core Location and MapKit

  • Core Location
    • Framework for managing location and heading
      • No user-interface
    • Basic object is CLLocation
      • Properties: coordinate, altitude, horizontal/verticallAccuracy, timestamp, speed, course
  • The more accuracy you request, the more battery will be used
  • CLLocationManager
    • Check if the hardware you are on/user supports the kind of location updating you want
    • Create a CLLocationManager instance and set the delegate to receive updates
    • Configure the manager according to what kind of location updating you want
    • Start the manager monitoring for location changes
  • Kinds of location monitoring
    • Accuracy-based continual updates
    • Updates only when “significant” changes in location occur
    • Region-based updates
    • Heading monitoring
  • Asking CLLocationManager what your hardware can do
    • class func authorizationStatus() -> CLAuthorizationStatus // Authorized, Denied or Restricted
    • class func locationServicesEnabled() -> Bool // user enabled (or not) locations for your app
  • You must add an Info.plist entry
    • NSLocationWhenInUseUsageDescription
    • NSLocationAlwaysUsageDescription
  • Error reporting to the delegate
    • func locationManager(CLLocationManager, didFailWithError: NSError)
    • Not always a fatal thing, so pay attention to this delegate method
  • 也可以进行后台更新
  • Map Kit
    • UI, can have annotations on it
    • Each annotation is a coordinate, a title and a subtitle
    • Annotation can have a callout. It appears when the annotation view is clicked
    • import MapKit
    • 地图部分也是玩法很多的，需要仔细研究研究
  • MKLocalSearch
    • Can search by natural language strings asynchronously
  • MKDirections, MKRoute, MKPolyline
  • Overlays, MKOverlayView
  • callout 只能代码配合 storyboard 实现，因为 storyboard 压根不会显示这个 callout

trax Demo

源码：Trax swift2版本，修改了不少错误

参考：Swift 千金方 2 - Stanford CS193p 学习笔记