My iPhone app registers for significant location change. When on location change is called, I start beacon region monitoring for all the beacon in certain range of user's location.
My app needs to identify that user has entered into a beacon region (irrespective of whether app is running or not). To achieve this, we did following things:
-- set notifyEntryStateOnDisplay flag to true for beacon regions:
beaconRegion.notifyEntryStateOnDisplay = true;
-- set Required background modes in pList to bluetooth-central. for ref. this link
I am not sure what got it working. But it turns out our app does not turn location services off, once started.
Is it possible to get significant location change update and beacon region entered update when location service is off?
Do I need to set Required background modes to get this working in background?
When you using iBeacon to monitor for specific region it will always display location icon on status bar, even when app is closed.
To disable location service for your app try to call method bellow for all you registered regions when going to background:
- (void)stopMonitoringForRegion:(CLRegion *)region
And to use iBeacon in background you actually need not "bluetooth-central" mode but "location".
You do not need to keep background mode - location updates ON for beacon ranging.
For background execution, just use UIBackgroundTaskIdentifier and your code will work in background as well.
check my answer iBeacon ranging in the background? here.
Related
After my app is killed I want to relaunch the app based on the location.speed paramater, I mean to say when the device speed is>5kmph I want my app to get open and one button needs to be clicked programatically?
NOT POSSIBLE.
You can not execute part of code when you process is killed. Its as simple as that.
You can do this in android with background sevice which run even when you app gets killed because background service is different process. But iOS don't allow to create background service.
Set allowsBackgroundLocationUpdates = true
The default value is NO for allowsBackgroundLocationUpdates
If your app uses location in the background (without showing the blue status bar) you have to set allowsBackgroundLocationUpdates to YES in addition to setting the background mode capability in Info.plist. Otherwise location updates are only delivered in foreground. The advantage is that you can now have location managers with background location updates and other location managers with only foreground location updates in the same app. You can also reset the value to NO to change the behavior.
I am working on an app that records journeys by tracking the GPS. Everything is working fine in background if we start the process from the foreground (by tapping the button "Start Journey").
Now the idea is start record these journeys automatically triggered by a iBeacon. When the iPhone gets inside of a beacon region, the app is detecting this and calls the function LocationManager.StartUpdatingLocation();
PROBLEM:
Using iBeacons from background, we only get 10 seconds ranging and that is the same figure I have got to get location updates from GPS.
All I need is detect I am inside of beacon region, start GPS and keep it running, and only disable the GPS when I am outside of the region.
Unfortunately, you can use CoreLocation geofences in the background, but you can't get fine GPS updates continually. This isn't a Xamarin thing -- it is an iOS restriction.
I wrote the blog post that #RobertN referenced about extending background beacon ranging to 3 minutes. But I don't think this is much help to you because you want to do get GPS updates continually, which Apple simply does not allow.
We actually recently wanted to implement this behavior in one of our apps too, and found that if we start significant location updates (startMonitoringSignificantLocationChanges) in the foreground, then we're able to start regular location updates (startUpdatingLocation) in the background, in our didEnterRegion implementation.
(Naturally, your app needs the "always" authorization to access Location Services, and the "Location updates" Background Mode enabled.)
Our app is still pending review, so whether that's a bug or a feature of Core Location, and whether Apple is okay with that, remains to be seen.
The best explanation to this I seen can extend that 10 seconds to 3 minutes, but that is it... App rejection is an issue with continuous background operation unless your app truly is reviewed as a Navigation app:
A second approach involves tracking the beacon in the background,
noting its estimated distance, and only triggering an action when the
beacon is estimated to be within a specific range. This approach is
problematic on iOS, because CoreLocation generally allows only 10
seconds of ranging time when an app is in the background. If a beacon
is first detected at 50 meters, and a person is approaching the beacon
at one meter per second, the mobile device will still be 40 meters
away when iOS suspends the app and stops it from ranging.
The good news is that it is possible to extend background ranging time
on iOS. If your app is a navigation app, you can specify location
updates in the “Required background modes” in your Info.plist. But
this approach makes it harder to get AppStore approval -- you have to
convince reviewers that your app is providing navigation services to
the user. This probably isn’t true for many apps that simply want to
use beacons to trigger at a specific distance.
Fortunately, you can still extend background ranging time without
requesting special background modes. The time you can get is limited
-- only three minutes. But this clock restarts each time your app is woken up in the background, meaning you can get an extra three minutes
of ranging time each time your app detects a beacon (enters a beacon
region) or stops seeing beacons (exits a beacon region.)
Via: http://developer.radiusnetworks.com/2014/11/13/extending-background-ranging-on-ios.html
I'm developing an iPhone app that will need to keep updating location even when app is in the background.
What I do is:
set background mode for Location Update
set desiredAccuracy = kCLLocationAccuracyBestForNavigation
implement -(void) locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations;
call [locationManager startUpdatingLocation]
While the app enter background, it will keep update the location by about only 10 minutes. and then, the update is stop.
Do someone know why?
How can I do a long time location update in background?
Thanks!
From Apple Documentation
You enable location support from the Background modes section of the Capabilities tab in your Xcode project. (You can also enable this support by including the UIBackgroundModes key with the location value in your app’s Info.plist file.) Enabling this mode does not prevent the system from suspending the app, but it does tell the system that it should wake up the app whenever there is new location data to deliver. Thus, this key effectively lets the app run in the background to process location updates whenever they occur.
It seems like setting the background mode should be enough. I got this to work in an app I'm working on, the only difference I see is that I have the pausesLocationUpdatesAutomatically set to NO.
To solve this in my QT app when the App would go into the background I would stopUpdatingLocation, decrease the accuracy from Best to kCLLocationAccuracyNearestTenMeters AND set a distance filter from None to 50 meters, then startUpdatingLocation.
You could try a lower filter if you need more granular location data.
With the M7 chip in the latest iOS devices one can get programmatically notified as the user goes from stationary to running, walking, etc using CMMotionActivityManager. Stava and Runkeeper have both used this to auto-pause GPS polling (shut off the GPS antenna) when it detects the user isn't moving via the M7, and then re-enable GPS updates once they are moving again. It is able to do this while the app is in the background state, which is the key here.
The issue I run into while duplicating this functionality is that if I turn off GPS updates while my app is in the background I stop receiving activity updates, and can no longer detect when the user moves again via the M7 to turn the GPS back on.
If I leave the GPS running the whole time I'll continue to get movement updates from Core Motion the entire time the app is in the background.
I'm assuming they aren't playing white-noise or some other cheap trick to stay active. How did they go about this?
RunKeeper actually does use the audio trick to stay awake. If you open up the app package and check their Info.plist you will see that it registers for the background audio mode. This is how they pull off periodic audio notifications of your distance, speed, and pace. It is also how they stay awake during your run while minimizing battery drain.
If you noticed that the Location Services icon (the triangle in the status bar) disappears completely while using RunKeeper then they definitely are not using any type of location tracking to accomplish background execution. Even activating geo-fences and significant location change monitoring would cause the Location Services icon to appear.
They also aren't using the M7 to stay awake because it doesn't work that way. An update from the M7-related CoreMotion APIs will not wake up your app from sleep. When they app does wake up they would be able to query the Motion Activity and Step history and maybe try to compute something, but I doubt it would be all that accurate.
Finally you should note that the Auto-pause APIs were introduced in iOS 6 before the release of the iPhone 5s and M7 chip. They are orthogonal concepts.
have you considered experimenting with
application:performFetchWithCompletionHandler:
in the app delegate? You can't control how often it is called, but depending on the app, it can be every ~15 minutes. You can then launch the CMMotionActivityManager from there to query M7 results.
It's not entirely clear what functionality you are trying to replicate, but the M7 chip records all of the activity, regardless of whether your app is running. So you can simply query in the background and update step totals or activity type totals.
What I noticed when you turn off GPS, app will not execute any code in background for iOS 7, app looks like in inactive state. So better while moving to background use startMonitoringSignificantLocationChanges and also get updates from your location manager. Means simultenoulsy use both service startUpdatingLocation on user state change and startMonitoringSignificantLocationChanges in Background.
So when user Turn on GPS, while you used startMonitoringSignificantLocationChanges your app will receive
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
Better check here in background itself what wrong with CoreMotion Framework. And try to restart it.
Because wihtout M7 chip device I am able to read Accelerometer reading in such case.
If your location manager is working in Active mode, to enable background mode you need to do this three steps:
Check that [Target / Capabilities / Background Modes / Location updates] is enabled.
[locationManager requestAlwaysAuthorization];
locationManager.allowsBackgroundLocationUpdates = YES;
First, check if you have set up the background behave of your app.
Go to target - capabilities section and check Background mode for location updates.
I have a problem with my App based in Region Monitoring in iOS;
Suppose that I have a Monitored Region with 300 meters radius, and my location is 350 meters off the center of that region (but I am into a car moving get closer to my region).
If I close my App in that moment the GPS is turned Off instantly and the method "didEnterRegion" is never called. This problem doesn't happen if my location is farther to my region monitored (for example 500 meters away)
Is possible to fix this? I tried with "Background modes" setting the "Required location services" in background, but this make to use the GPS instead "Region Monitoring" and the GPS never stops.
The problem with Region Monitoring is that this function never works when the user is already "inside the region", then this causes a lot of problems for the in time notification.
First, you don't need background mode for region monitoring to work, region monitoring will continue to function even if you Sleep your device(pressing the top button). Plus Apple can reject your app if you don't use BG mode according to how they need it.
For your issue, if you are already inside and you are not getting a didEnterRegion for whatever reasons, you should use a backup plan. In your CLRegion class you can call containsCoordinate to see if you are inside the region.
You did not get a didEnterRegion call probably for some reason your add region gets reinitialized. I.e. you have re-added your region.