我希望在应用后台获取用户位置。如果我使用计时器9秒或更短秒，如果我使用10秒甚至更长时间我无法获得用户位置...
我的代码（AppDelegate.swift）：
import UIKit
import CoreLocation
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, CLLocationManagerDelegate {
var window: UIWindow?
var backgroundTaskIdentifier:UIBackgroundTaskIdentifier = UIBackgroundTaskInvalid
var myTimer: NSTimer?
var locationManager = CLLocationManager()
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
// Override point for customization after application launch.
return true
}
func isMultitaskingSupported()->Bool{
return UIDevice.currentDevice().multitaskingSupported
}
func timerMethod(sender: NSTimer){
let backgroundTimerRemainig = UIApplication.sharedApplication().backgroundTimeRemaining
self.locationManager.startUpdatingLocation()
if backgroundTimerRemainig == DBL_MAX{
println("test1");
}else{
println("test");
self.locationManager.delegate = self
self.locationManager.startUpdatingLocation()
}
}
func applicationWillResignActive(application: UIApplication) {
}
func applicationDidEnterBackground(application: UIApplication){
if isMultitaskingSupported() == false{
return
}
myTimer = NSTimer.scheduledTimerWithTimeInterval(60.0,
target: self,
selector: "timerMethod:",
userInfo: nil,
repeats: true)
backgroundTaskIdentifier = UIApplication.sharedApplication().beginBackgroundTaskWithExpirationHandler { () -> Void in
UIApplication.sharedApplication().endBackgroundTask(self.backgroundTaskIdentifier)
}
}
func endBackgroundTask(){
let mainQueue = dispatch_get_main_queue()
dispatch_async(mainQueue, {[weak self] in
if let timer = self!.myTimer{
timer.invalidate()
self!.myTimer = nil
UIApplication.sharedApplication().endBackgroundTask(self!.backgroundTaskIdentifier)
self!.backgroundTaskIdentifier = UIBackgroundTaskInvalid
}
})
}
func applicationWillEnterForeground(application: UIApplication) {
if backgroundTaskIdentifier != UIBackgroundTaskInvalid{
endBackgroundTask()
}
}
func applicationDidBecomeActive(application: UIApplication) {
}
func applicationWillTerminate(application: UIApplication) {
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}
func locationManager(manager: CLLocationManager!, didUpdateToLocation locations:[AnyObject]) {
var latValue = locationManager.location.coordinate.latitude
var lonValue = locationManager.location.coordinate.longitude
}
}
当我使用10秒甚至更长时间时，为什么我无法获得用户位置？