I am trying to implement the suggestions given in this post.
我正在努力落实这篇文章中提出的建议。
Unfortunately the steps are not clear to me. I tried implementing those suggestions, but the backgroundTimeRemaining continues to decrease even after I start and stop locationServices. This is how I developed it:
不幸的是,我不清楚这些步骤。我尝试执行这些建议,但即使在启动和停止locationServices之后,后台时间管理仍然继续减少。我就是这样发展的:
- (void)applicationDidEnterBackground:(UIApplication *)application {
UIApplication* app = [UIApplication sharedApplication];
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[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.
self.timer = nil;
[self initTimer];
});
}
initTimer:
initTimer:
- (void)initTimer {
// Create the location manager if this object does not
// already have one.
if (nil == self.locationManager)
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.delegate = self;
[self.locationManager startMonitoringSignificantLocationChanges];
if (self.timer == nil) {
self.timer = [NSTimer scheduledTimerWithTimeInterval:0.3
target:self
selector:@selector(checkUpdates:)
userInfo:nil
repeats:YES];
}
}
checkUpdates:
checkUpdates:
- (void)checkUpdates:(NSTimer *)timer{
UIApplication* app = [UIApplication sharedApplication];
double remaining = app.backgroundTimeRemaining;
if(remaining < 580.0) {
[self.locationManager startUpdatingLocation];
[self.locationManager stopUpdatingLocation];
[self.locationManager startMonitoringSignificantLocationChanges];
}
DbgLog(@"Reminaing %f", app.backgroundTimeRemaining);
}
Does anyone have a suggestion on what might be wrong in my code? Both initTimer and checkUpdates are being called, but only during for the background execution time (+- 10 Mins). I want the app to update the location every n minutes "forever".
有人对我的代码有什么问题有什么建议吗?initTimer和checkUpdates都被调用,但只在后台执行时间(+- 10分钟)期间调用。我想让这个应用每n分钟更新一次位置“永远”。
My app's UIBackgroundModes is set to location.
我的应用程序的uibackgroundmode被设置为location。
UPDATE:
更新:
I am now resetting the timer on didUpdateToLocation and didFailWithError. But still the backgroundTimeRemaining keeps decreasing:
我现在在didUpdateToLocation和didFailWithError上重新设置计时器。但背景时间效应仍在不断减少:
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation {
NSLog(@"Did Update Location = %f / %f", [newLocation coordinate].latitude, [newLocation coordinate].longitude);
UIApplication* app = [UIApplication sharedApplication];
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[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.
[self initTimer];
});
}
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
[self.locationManager stopUpdatingLocation];
UIApplication* app = [UIApplication sharedApplication];
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask];
bgTask = UIBackgroundTaskInvalid;
}];
// Start the long-running task and return immediately.
[self initTimer];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
// Do the work associated with the task.
});
}
I am also invalidating the timer:
我也在废除计时器:
- (void)checkUpdates:(NSTimer *)timer{
UIApplication* app = [UIApplication sharedApplication];
double remaining = app.backgroundTimeRemaining;
if(remaining < 580.0 && remaining > 570.0) {
[self.timer invalidate];
self.timer = nil;
[self.locationManager startUpdatingLocation];
[self.locationManager stopUpdatingLocation];
}
DbgLog(@"*************************Checking for updates!!!!!!!!!!! Reminaing %f", app.backgroundTimeRemaining);
}
4 个解决方案
#1
10
To anyone else having a nightmare of a time trying to figure this one out, I have a simple solution.
对于任何想要解决这个问题的人来说,我有一个简单的解决方案。
- Study the example from raywenderlich.com. The sample code works perfectly, but unfortunately there's no timer during background location. This will run indefinitely.
- 研究来自raywenderlich.com的例子。示例代码工作得很好,但不幸的是,在后台位置没有计时器。这将运行下去。
-
Add timer by using this code snippet:
使用此代码片段添加计时器:
-(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.
只是别忘了在info.plist中添加“位置更新的应用程序寄存器”。
#2
9
After some days trying all possible solutions I was finally able to make it work. Here is what was wrong in my solution:
经过几天的努力,我终于能够成功。以下是我的解决方案中存在的问题:
- I need to setup 2 UIBackgroundTaskIdentifiers, one for the timer, and another one for the locationManager
- 我需要设置两个uibackgroundtaskidentifier,一个用于计时器,另一个用于locationManager
On my solution, just add:
我的解决方案是:
UIApplication *app = [UIApplication sharedApplication];
bgTask2 = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask2];
bgTask2 = UIBackgroundTaskInvalid; }];
self.locationManager.delegate = self;
[self.locationManager startUpdatingLocation];
#3
4
Once you're in the background you can only have 10 minutes of additional time. There is no way to extend that. You should use the location background services instead.
一旦你在后台,你只能有10分钟的额外时间。这是无法延伸的。您应该使用位置后台服务。
#4
0
Working Code(Entire Stepwise Code) Modified scurioni's code
工作代码(完整的逐步代码)修改了scurioni的代码
Step 1
步骤1
- Go to project -> Capabilities -> Background Modes -> select Location updates.
- 去项目->功能->后台模式->选择位置更新。
- Go to Project -> Info -> add a key NSLocationAlwaysUsageDescription with an optional string.
- 转到Project -> Info ->,添加一个带有可选字符串的关键NSLocationAlwaysUsageDescription。
Step 2
步骤2
Add this code to AppDelegate.m
将此代码添加到AppDelegate.m中
@interface AppDelegate ()<CLLocationManagerDelegate>
@property (strong, nonatomic) CLLocationManager *locationManager;
@property (strong, nonatomic) NSTimer *timer;
@end
Step 3 Add This Code in to applicationDidEnterBackground method in AppDelegate.m
步骤3将此代码添加到AppDelegate.m中的applicationDidEnterBackground方法中
- (void)applicationDidEnterBackground:(UIApplication *)application {
UIApplication *app = [UIApplication sharedApplication];
__block UIBackgroundTaskIdentifier bgTaskId =
[app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTaskId];
bgTaskId = UIBackgroundTaskInvalid;
}];
dispatch_async( dispatch_get_main_queue(), ^{
self.timer = nil;
[self initTimer];
[app endBackgroundTask:bgTaskId];
bgTaskId = UIBackgroundTaskInvalid;
});
}
- (void)initTimer {
if (nil == self.locationManager)
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.delegate = self;
[self.locationManager requestAlwaysAuthorization];
[self.locationManager startMonitoringSignificantLocationChanges];
if (self.timer == nil) {
self.timer = [NSTimer scheduledTimerWithTimeInterval:0.3
target:self
selector:@selector(checkUpdates:)
userInfo:nil
repeats:YES];
}
}
- (void)checkUpdates:(NSTimer *)timer{
UIApplication *app = [UIApplication sharedApplication];
double remaining = app.backgroundTimeRemaining;
if(remaining < 580.0) {
[self.locationManager startUpdatingLocation];
[self.locationManager stopUpdatingLocation];
[self.locationManager startMonitoringSignificantLocationChanges];
}
}
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation {
NSLog(@"Did Update Location = %f / %f", [newLocation coordinate].latitude, [newLocation coordinate].longitude);
[self updateLocationWithLatitude:[newLocation coordinate].latitude andLongitude:[newLocation coordinate].longitude];
UIApplication* app = [UIApplication sharedApplication];
__block UIBackgroundTaskIdentifier bgTask =
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask];
bgTask = UIBackgroundTaskInvalid;
}];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[self initTimer];
});
}
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
[self.locationManager stopUpdatingLocation];
UIApplication *app = [UIApplication sharedApplication];
__block UIBackgroundTaskIdentifier bgTask =
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask];
bgTask = UIBackgroundTaskInvalid;
}];
[self initTimer];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
// Do the work associated with the task
});
}
-(void)updateLocationWithLatitude:(CLLocationDegrees)latitude
andLongitude:(CLLocationDegrees)longitude{
//Here you can update your web service or back end with new latitude and longitude
}
#1
10
To anyone else having a nightmare of a time trying to figure this one out, I have a simple solution.
对于任何想要解决这个问题的人来说,我有一个简单的解决方案。
- Study the example from raywenderlich.com. The sample code works perfectly, but unfortunately there's no timer during background location. This will run indefinitely.
- 研究来自raywenderlich.com的例子。示例代码工作得很好,但不幸的是,在后台位置没有计时器。这将运行下去。
-
Add timer by using this code snippet:
使用此代码片段添加计时器:
-(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.
只是别忘了在info.plist中添加“位置更新的应用程序寄存器”。
#2
9
After some days trying all possible solutions I was finally able to make it work. Here is what was wrong in my solution:
经过几天的努力,我终于能够成功。以下是我的解决方案中存在的问题:
- I need to setup 2 UIBackgroundTaskIdentifiers, one for the timer, and another one for the locationManager
- 我需要设置两个uibackgroundtaskidentifier,一个用于计时器,另一个用于locationManager
On my solution, just add:
我的解决方案是:
UIApplication *app = [UIApplication sharedApplication];
bgTask2 = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask2];
bgTask2 = UIBackgroundTaskInvalid; }];
self.locationManager.delegate = self;
[self.locationManager startUpdatingLocation];
#3
4
Once you're in the background you can only have 10 minutes of additional time. There is no way to extend that. You should use the location background services instead.
一旦你在后台,你只能有10分钟的额外时间。这是无法延伸的。您应该使用位置后台服务。
#4
0
Working Code(Entire Stepwise Code) Modified scurioni's code
工作代码(完整的逐步代码)修改了scurioni的代码
Step 1
步骤1
- Go to project -> Capabilities -> Background Modes -> select Location updates.
- 去项目->功能->后台模式->选择位置更新。
- Go to Project -> Info -> add a key NSLocationAlwaysUsageDescription with an optional string.
- 转到Project -> Info ->,添加一个带有可选字符串的关键NSLocationAlwaysUsageDescription。
Step 2
步骤2
Add this code to AppDelegate.m
将此代码添加到AppDelegate.m中
@interface AppDelegate ()<CLLocationManagerDelegate>
@property (strong, nonatomic) CLLocationManager *locationManager;
@property (strong, nonatomic) NSTimer *timer;
@end
Step 3 Add This Code in to applicationDidEnterBackground method in AppDelegate.m
步骤3将此代码添加到AppDelegate.m中的applicationDidEnterBackground方法中
- (void)applicationDidEnterBackground:(UIApplication *)application {
UIApplication *app = [UIApplication sharedApplication];
__block UIBackgroundTaskIdentifier bgTaskId =
[app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTaskId];
bgTaskId = UIBackgroundTaskInvalid;
}];
dispatch_async( dispatch_get_main_queue(), ^{
self.timer = nil;
[self initTimer];
[app endBackgroundTask:bgTaskId];
bgTaskId = UIBackgroundTaskInvalid;
});
}
- (void)initTimer {
if (nil == self.locationManager)
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.delegate = self;
[self.locationManager requestAlwaysAuthorization];
[self.locationManager startMonitoringSignificantLocationChanges];
if (self.timer == nil) {
self.timer = [NSTimer scheduledTimerWithTimeInterval:0.3
target:self
selector:@selector(checkUpdates:)
userInfo:nil
repeats:YES];
}
}
- (void)checkUpdates:(NSTimer *)timer{
UIApplication *app = [UIApplication sharedApplication];
double remaining = app.backgroundTimeRemaining;
if(remaining < 580.0) {
[self.locationManager startUpdatingLocation];
[self.locationManager stopUpdatingLocation];
[self.locationManager startMonitoringSignificantLocationChanges];
}
}
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation {
NSLog(@"Did Update Location = %f / %f", [newLocation coordinate].latitude, [newLocation coordinate].longitude);
[self updateLocationWithLatitude:[newLocation coordinate].latitude andLongitude:[newLocation coordinate].longitude];
UIApplication* app = [UIApplication sharedApplication];
__block UIBackgroundTaskIdentifier bgTask =
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask];
bgTask = UIBackgroundTaskInvalid;
}];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[self initTimer];
});
}
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
[self.locationManager stopUpdatingLocation];
UIApplication *app = [UIApplication sharedApplication];
__block UIBackgroundTaskIdentifier bgTask =
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask];
bgTask = UIBackgroundTaskInvalid;
}];
[self initTimer];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
// Do the work associated with the task
});
}
-(void)updateLocationWithLatitude:(CLLocationDegrees)latitude
andLongitude:(CLLocationDegrees)longitude{
//Here you can update your web service or back end with new latitude and longitude
}