In app when using NSTimer then this timer is consume battery of iOS device..?
We are schedule this NSTimer for every 30 SEC in app whether app in foreground or background.
In this timer we just check internet availability by sending request to host.
You can use this nice and simple block based, drop dead Reachability class to get notified whenever there is any change in network availability.
https://github.com/tonymillion/Reachability
Do not use a Timer to get notified for network connection changes.
Related
I'm working on VPN for iOS. And i want to add ability to pause vpn to 5, 15 min and a hour. It means when user for example clicks on pause 15 min vpn disconnected and start connection in 15 min. But i don't understand how to schedule connection task.
I tried to do it with Timer but timer stop working when app in background.
I thought about BGTaskScheduler but how i understand in this case OS decides when start task and i will not be able to guarantee that i will start vpn connection in time.
Also i thought about silent PUSH notifications but i not sure that it is a good solution.
Can anyone suggest how can i solve this task more accurate?
In my application, the user needs to connect the device wifi to another wifi via the iOS settings. I want my app to remain in the background for some time(like 5 min max) without getting suspended, until the user connects to the other network and returns to the application.
I observe that my application gets removed from background during switching the device wifi. The application doesn't remain active in the background.
How do I keep the iOS application (iOS 9+) in background for some time i.e 5 min?
Apps moving to the background are expected to put themselves into a
quiescent state as quickly as possible so that they can be suspended
by the system. If your app is in the middle of a task and needs a
little extra time to complete that task, it can call the
beginBackgroundTaskWithName:expirationHandler: or
beginBackgroundTaskWithExpirationHandler: method of the UIApplication
object to request some additional execution time. Calling either of
these methods delays the suspension of your app temporarily, giving it
a little extra time to finish its work. Upon completion of that work,
your app must call the endBackgroundTask: method to let the system
know that it is finished and can be suspended.
(source: https://developer.apple.com/library/content/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/BackgroundExecution/BackgroundExecution.html)
Read iOS Backgrounding with Tasks .
The time App will be in background in 10 minutes that is 600 seconds.
You can know time remaining using the code
NSLog(#"Time Remaining: %f", [[UIApplication sharedApplication] backgroundTimeRemaining]);
Since your need is just turning wifi on- It may take less than 10 minutes i think.
Hope my answer is Clear and Helpful.
How to trigger a method for every hour irrespective to application is active or background or terminated.
The method should trigger every hour.
NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:60*60 target:self selector:#selector(callYourMethod:) userInfo:nil repeats:YES];
I heard that the NSTimer will not work after 10 min of time.
Can any one advice me how to activate a method that will trigger a method every one hours in iOS Objecitve-C
Managing this type of task locally is a bad idea. You can't afford to NSTimer or GCD because they're designed to be used when the application is in the foreground state.
When you're in background, the app can invalidate timers or dispatch methods after some minutes and - anyway - at the discretion of iOS. If the system needs to free memory for other apps or optimise the battery consumption, it puts the app in the Suspended state.
You can force the awakening of an app from the Closed or Suspended state only by using VoIP Notifications with the PushKit Framework, introduced in iOS 8. Note that you should use this type of notifications only in the case you implement VoIP services in you app. This framework is badly documented, first by Apple but also on other sites like StackOverflow. I suggest you to follow this tutorial by Pierre-Marc Airoldi that guides you step by step in order to build a fully functional demo of an app that uses VoIP Services.
Note that standard notifications don't do anything when you receive them: the methods in the AppDelegate will be fired only if you click on the notification. If you don't want to show the notification to the user, send it without a message; it won't be displayed on screen but it will be received as well.
I'm currently working on an app that should periodically (every minute) perform a network call while the app is backgrounded or killed. This network call will send information to our API.
Is this possible on iOS? How?
Assuming you want a service like a Social Media app, where it will check in the background every minute for new activity, you should use background execution.
Have a look at this Background Execution tutorial and the Apple Reference for Background Execution.
So I need this app to run timer for more than 3 minutes, and play a sound like very 45 seconds, most of the solutions here are just for less than 3 minutes on iOS. Is there a way to make it run all the time, unless the app stops?
After the research, I guess the solution is implement beginBackgroundTaskWithExpirationHandler
and stops it by giving a handler and set location update on plist?
As for audio, besides setting the plist, anything else need to do to play audio?
Swift how to use NSTimer background?
iphone - NSTimers in background
Run app for more than 10 minutes in background
No, in order to save all of us from apps that kill our batteries, Apple does not allow apps to continue to run in the background for more than a few minutes. There are only very special limitations (music playing apps, VOIP, navigation apps, etc.) which permit ongoing operation. In terms of details, this is described in About the Background Execution Sequence.
If you want to notify user of something at some future time, you can use local notifications. When you do this, though, you don't control whether your app restarts or not. Only if the user taps on the notification (assuming they even granted your app notification privileges at all), will the app be reopened. For more information, refer the the local notification discussions in UserNotification framework documentation. But note, this is not intended for alerts every 45 seconds, but rather for a significant notification scheduled for some future time.
For discussion of how one might marry local notifications with timers, see swift NSTimer in Background and this follow up question swift calculate time for timers running in background.