Background Modes in iOS

Being responsive is a need for every app. Users want to have apps which have their content ready when they open it, so developers should use Background Modes to make their apps more user friendly.

Turning on the Background Modes capability

1. Go to Xcode and open your project.
2. In your app target, navigate to Capabilities tab. 3. Turn on Background Modes.

Background Fetch

Background fetch is a new mode that lets your app appear always up-to-date with the latest information while minimizing the impact on battery. You could download feeds within fixed time intervals with this capability.

To get started:
1- Check Background Fetch in capabilities screen in Xcode.
2- In application(_:didFinishLaunchingWithOptions:) method in AppDelegate, add:

Swift

UIApplication.shared.setMinimumBackgroundFetchInterval(UIApplicationBackgroundFetchIntervalMinimum)

Objective-C

[[UIApplication shared]
setMinimumBackgroundFetchInterval:UIApplicationBackgroundFetchIntervalMinimum]

Instead of UIApplicationBackgroundFetchIntervalMinimum, you could use any CGFloat value to set fetch intervals.

3- You must implement application(_:performFetchWithCompletionHandler:). Add that to your AppDelegate:

Swift

func application(_ application: UIApplication, performFetchWithCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {// your code here}