我正在寻找一种方法来获得背景位置更新每n分钟在我的iOS应用程序。我使用的是iOS 4.3,解决方案应该适用于未越狱的iphone。

我尝试/考虑了以下选项:

CLLocationManager startUpdatingLocation/startMonitoringSignificantLocationChanges: This works in the background as expected, based on the configured properties, but it seems not possible to force it to update the location every n minutes NSTimer: Does work when the app is running in the foreground but doesn't seem to be designed for background tasks Local notifications: Local notifications can be scheduled every n minutes, but it's not possible to execute some code to get the current location (without the user having to launch the app via the notification). This approach also doesn't seem to be a clean approach as this is not what notifications should be used for. UIApplication:beginBackgroundTaskWithExpirationHandler: As far as I understand, this should be used to finish some work in the background (also limited in time) when an app is moved to the background rather than implementing "long-running" background processes.

如何实现这些定期的后台位置更新?


当前回答

给其他做噩梦的人想想这个。我有一个简单的解决办法。

look this example from raywenderlich.com-> have sample code, this works perfectly, but unfortunately no timer during background location. this will run indefinitely. Add timer by using : -(void)applicationDidEnterBackground { [self.locationManager stopUpdatingLocation]; UIApplication* app = [UIApplication sharedApplication]; bgTask = [app beginBackgroundTaskWithExpirationHandler:^{ [app endBackgroundTask:bgTask]; bgTask = UIBackgroundTaskInvalid; }]; self.timer = [NSTimer scheduledTimerWithTimeInterval:intervalBackgroundUpdate target:self.locationManager selector:@selector(startUpdatingLocation) userInfo:nil repeats:YES]; } Just don't forget to add "App registers for location updates" in info.plist.

其他回答

现在iOS6已经发布了,永远运行位置服务的最好方法是……

- (void)applicationWillResignActive:(UIApplication *)application
{
/*
 Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
 Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
 */

NSLog(@"to background");

app.isInBackground = TRUE;

UIApplication *app = [UIApplication sharedApplication];

// Request permission to run in the background. Provide an
// expiration handler in case the task runs long.
NSAssert(bgTask == UIBackgroundTaskInvalid, nil);

bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
    // Synchronize the cleanup call on the main thread in case
    // the task actually finishes at around the same time.
    dispatch_async(dispatch_get_main_queue(), ^{

        if (bgTask != UIBackgroundTaskInvalid)
        {
            [app endBackgroundTask:bgTask];
            bgTask = UIBackgroundTaskInvalid;
        }
    });
}];

// Start the long-running task and return immediately.
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

    // Do the work associated with the task.

    locationManager.distanceFilter = 100;
    locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters;
    [locationManager startMonitoringSignificantLocationChanges];
    [locationManager startUpdatingLocation];

    NSLog(@"App staus: applicationDidEnterBackground");
    // Synchronize the cleanup call on the main thread in case
    // the expiration handler is fired at the same time.
    dispatch_async(dispatch_get_main_queue(), ^{
        if (bgTask != UIBackgroundTaskInvalid)
        {
            [app endBackgroundTask:bgTask];
            bgTask = UIBackgroundTaskInvalid;
        }
    });
});

NSLog(@"backgroundTimeRemaining: %.0f", [[UIApplication sharedApplication] backgroundTimeRemaining]);

}

就像这样测试:

我打开应用程序,进入后台,几分钟后开车。然后我回家1小时,再次开始移动(没有再次打开应用程序)。重新开始定位。然后停了两个小时,又重新开始。一切都好了……

不要忘记在iOS6中使用新的位置服务

- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{   
    CLLocation *loc = [locations lastObject];

    // Lat/Lon
    float latitudeMe = loc.coordinate.latitude;
    float longitudeMe = loc.coordinate.longitude;
}

附件是基于以下的Swift解决方案:

在info.plist中定义位置更新的App寄存器

保持locationManager一直运行

在BestForNavigation和threekm之间切换kCLLocationAccuracy(5秒获得位置),以避免电池耗尽

这个例子在前台每1分钟更新一次位置,在后台每15分钟更新一次位置。

这个例子适用于运行在iOS 7设备上的Xcode 6 Beta 6。

在App委托中(mapView是一个指向mapView控制器的可选选项)

func applicationDidBecomeActive(application: UIApplication!) {
    if appLaunched! == false { // Reference to mapView used to limit one location update per timer cycle
        appLaunched = true
        var appDelegate = UIApplication.sharedApplication().delegate as AppDelegate
        var window = appDelegate.window
        var tabBar = window?.rootViewController as UITabBarController
        var navCon = tabBar.viewControllers[0] as UINavigationController
        mapView = navCon.topViewController as? MapViewController
    }
    self.startInitialPeriodWithTimeInterval(60.0)
}

func applicationDidEnterBackground(application: UIApplication!) {
    self.startInitialPeriodWithTimeInterval(15 * 60.0)
}

func startInitialPeriodWithTimeInterval(timeInterval: NSTimeInterval) {
    timer?.invalidate() // reset timer
    locationManager?.desiredAccuracy = kCLLocationAccuracyBestForNavigation
    timer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: Selector("getFirstLocationUpdate:"), userInfo: timeInterval, repeats: false)
}

func getFirstLocationUpdate(sender: NSTimer) {
    let timeInterval = sender.userInfo as Double
    timer?.invalidate()
    mapView?.canReportLocation = true
    timer = NSTimer.scheduledTimerWithTimeInterval(timeInterval, target: self, selector: Selector("waitForTimer:"), userInfo: timeInterval, repeats: true)
}

func waitForTimer(sender: NSTimer) {
    let time = sender.userInfo as Double
    locationManager?.desiredAccuracy = kCLLocationAccuracyBestForNavigation
    finalTimer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: Selector("getLocationUpdate"), userInfo: nil, repeats: false)
}

func getLocationUpdate() {
    finalTimer?.invalidate()
    mapView?.canReportLocation = true
}

在mapView中(locationManager指向AppDelegate中的对象)

override func viewDidLoad() {
    super.viewDidLoad()
    var appDelegate = UIApplication.sharedApplication().delegate! as AppDelegate
    locationManager = appDelegate.locationManager!
    locationManager.delegate = self
    canReportLocation = true
}

  func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {
        if canReportLocation! {
            canReportLocation = false
            locationManager.desiredAccuracy = kCLLocationAccuracyThreeKilometers
        } else {
            //println("Ignore location update")
        }
    }

在iOS 8/9/10上,每5分钟更新一次后台位置,执行以下操作:

进入项目->能力->背景模式->选择位置更新 转到项目->信息->添加一个键NSLocationAlwaysUsageDescription空值(或可选的任何文本) 当你的应用程序在后台工作,并发送坐标到web服务或做任何事情,每5分钟实现如下代码。

我没有使用任何后台任务或计时器。我在我的iOS 8.1设备上测试了这段代码,我的应用程序在后台运行了几个小时。设备被锁定,代码一直正常运行。

@interface LocationManager () <CLLocationManagerDelegate>
@property (strong, nonatomic) CLLocationManager *locationManager;
@property (strong, nonatomic) NSDate *lastTimestamp;

@end

@implementation LocationManager

+ (instancetype)sharedInstance
{
    static id sharedInstance = nil;

    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        sharedInstance = [[self alloc] init];
        LocationManager *instance = sharedInstance;
        instance.locationManager = [CLLocationManager new];
        instance.locationManager.delegate = instance;
        instance.locationManager.desiredAccuracy = kCLLocationAccuracyBest; // you can use kCLLocationAccuracyHundredMeters to get better battery life
        instance.locationManager.pausesLocationUpdatesAutomatically = NO; // this is important
    });

    return sharedInstance;
}

- (void)startUpdatingLocation
{
    CLAuthorizationStatus status = [CLLocationManager authorizationStatus];

    if (status == kCLAuthorizationStatusDenied)
    {
        NSLog(@"Location services are disabled in settings.");
    }
    else
    {
        // for iOS 8
        if ([self.locationManager respondsToSelector:@selector(requestAlwaysAuthorization)])
        {
            [self.locationManager requestAlwaysAuthorization];
        }
        // for iOS 9
        if ([self.locationManager respondsToSelector:@selector(setAllowsBackgroundLocationUpdates:)])
        {
            [self.locationManager setAllowsBackgroundLocationUpdates:YES];
        }

        [self.locationManager startUpdatingLocation];
    }
}

- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
    CLLocation *mostRecentLocation = locations.lastObject;
    NSLog(@"Current location: %@ %@", @(mostRecentLocation.coordinate.latitude), @(mostRecentLocation.coordinate.longitude));

    NSDate *now = [NSDate date];
    NSTimeInterval interval = self.lastTimestamp ? [now timeIntervalSinceDate:self.lastTimestamp] : 0;

    if (!self.lastTimestamp || interval >= 5 * 60)
    {
        self.lastTimestamp = now;
        NSLog(@"Sending current location to web service.");
    }
}

@end

似乎stopUpdatingLocation是什么触发后台看门狗定时器,所以我在didUpdateLocation替换它:

     [self.locationManager setDesiredAccuracy:kCLLocationAccuracyThreeKilometers];
     [self.locationManager setDistanceFilter:99999];

这似乎有效地关闭了GPS。然后,背景NSTimer的选择器变成:

- (void) changeAccuracy {
[self.locationManager setDesiredAccuracy:kCLLocationAccuracyBest];
[self.locationManager setDistanceFilter:kCLDistanceFilterNone];
}

我所做的是每隔几分钟定期切换精度以获得高精度坐标,因为locationManager没有停止,backgroundtimerremain保持在其最大值。这将我的设备上的电池消耗从每小时~10%(在后台使用恒定的kCLLocationAccuracyBest)降低到每小时~2%

给其他做噩梦的人想想这个。我有一个简单的解决办法。

look this example from raywenderlich.com-> have sample code, this works perfectly, but unfortunately no timer during background location. this will run indefinitely. Add timer by using : -(void)applicationDidEnterBackground { [self.locationManager stopUpdatingLocation]; UIApplication* app = [UIApplication sharedApplication]; bgTask = [app beginBackgroundTaskWithExpirationHandler:^{ [app endBackgroundTask:bgTask]; bgTask = UIBackgroundTaskInvalid; }]; self.timer = [NSTimer scheduledTimerWithTimeInterval:intervalBackgroundUpdate target:self.locationManager selector:@selector(startUpdatingLocation) userInfo:nil repeats:YES]; } Just don't forget to add "App registers for location updates" in info.plist.