在我的应用中，我想定期在服务器上获取和上传位置。对于前景它工作正常，但对于背景它有问题，如下所述。这里要提一点我在前台使用不同的类，为背景使用单独的代码。
要在后台获取位置，请执行以下操作。它上传位置大约24 - 40小时，但在24-40小时后停止。我没有得到“willTerminate”事件。我还编写了代码来捕获全局执行，以便我可以记录SigKill，如果用户杀死我的应用程序但它也没有记录原因可能是我们无法捕获SigKill。
现在我被困住了，不知道该怎么办才能让我的应用程序在后台保持活着，定期上传位置。
//////////////////////////////// didfinish lauch ////// /////////////////////////
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.delegate = self;
return YES;
}
////////// **did enter background**
- (void) applicationDidEnterBackground:(UIApplication *)application
{
self.bgTask = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{
[[UIApplication sharedApplication] endBackgroundTask:self.bgTask];
self.bgTask = UIBackgroundTaskInvalid;
}];
timer = [[NSTimer scheduledTimerWithTimeInterval:8*60
target:self
selector:@selector(changeAccuracy)
userInfo:nil
repeats:YES] retain];
[self.locationManager startUpdatingLocation];
}
- (void) changeAccuracy
{
self.bCallbackStarted = NO;
[self.locationManager setDesiredAccuracy:kCLLocationAccuracyBest];
[self.locationManager setDistanceFilter:100];
}
///////// **did enter fore ground**
- (void)applicationWillEnterForeground:(UIApplication *)application
{
[self.locationManager stopUpdatingLocation];
}
////////// **did update location**
-(void)locationManager:(CLLocationManager *)lm didUpdateLocations:(NSArray *)locations
{
if (self.bCallbackStarted == YES) {
NSString* logStr = [NSString stringWithFormat:@"URLFilteringAppDelegate::didUpdateLocations not uploading location because self.bCallbackStarted == YES"];
LOGI(logStr)
return;
}
self.bCallbackStarted = YES;
[[AppUtility sharedInstance] setLocationStatus:YES];
CLLocation *location = [locations lastObject];
if(location.coordinate.latitude == 0 && location.coordinate.longitude == 0)
{
[UserSettings sharedInstance].Latitude = [NSString stringWithFormat:@"%@", @"Unavailable"];
[UserSettings sharedInstance].Longitude = [NSString stringWithFormat:@"%@", @"Unavailable"];
}
else
{
[UserSettings sharedInstance].Latitude = [NSString stringWithFormat:@"%.8f", location.coordinate.latitude];
[UserSettings sharedInstance].Longitude = [NSString stringWithFormat:@"%.8f", location.coordinate.longitude];
}
[[LocationManager sharedInstance] sendLocation];
/// this is set to save battery
[lm setDesiredAccuracy:kCLLocationAccuracyThreeKilometers];
[lm setDistanceFilter:99999];
}