Communicating and persisting data between apps with App Groups

by

Another benefit to App Groups is the ability to share a NSUserDefaults database. This also works for App Extensions (notification center widgets, custom keyboards, etc).

Initialize your NSUserDefaults object like this in all applications in the app group and they will share the database:

Objective-C:

[[NSUserDefaults alloc] initWithSuiteName:@"<group identifier>"];

Swift:

NSUserDefaults(suiteName: "<group identifier>")

Keep in mind everything from the [NSUserDefaults standardUserDefaults] database for each application will not carry over into this database.

The documentation gives a correct example as well (As of Beta 3).

And don’t forget to synchronize the database:

[yourDefaults synchronize];

More Related Contents:

  1. UIAlertController custom font, size, color
  2. How to force view controller orientation in iOS 8?
  3. iOS 8 UITableView separator inset 0 not working
  4. Base64 Decoding in iOS 7+
  5. How to debug iOS 8 extensions with NSLog?
  6. Error when adding input view to textfield iOS 8
  7. openURL not work in Action Extension
  8. can’t get correct value of keyboard height in iOS8
  9. How to determine the content size of a WKWebView?
  10. Unwind Segue not working in iOS 8
  11. iOS 8 SDK: modal UIWebView and camera/image picker
  12. Disable iOS8 Quicktype Keyboard programmatically on UITextView
  13. Xcode 6 keeps renaming my app’s directory in iOS8 simulator after each run.
  14. Rotation methods deprecated, equivalent of ‘didRotateFromInterfaceOrientation’?
  15. How to change UITableViewRowAction title color?
  16. iOS 8 UIActivityViewController and UIAlertController button text color uses window’s tintColor
  17. Hyperlinks in a UITextView
  18. launch containing app from iOS8 Custom Keyboard
  19. Why can’t I call the default super.init() on UIViewController in Swift?
  20. On iOS8, displaying my app in landscape mode will hide the status bar but on iOS 7 the status bar is displayed on both orientations
  21. @property/@synthesize equivalent in swift
  22. How to prevent status bar from overlapping content with hidesBarsOnSwipe set on UINavigationController?
  23. How do I calculate the UILabel height dynamically [duplicate]
  24. Generate JSON string from NSDictionary in iOS
  25. How to handle different orientations in iOS
  26. Clearing NSUserDefaults
  27. How can i get the name of image picked through photo library in iphone?
  28. What’s the UIScrollView contentInset property for?
  29. NSDateFormatter: Date according to currentLocale, without Year
  30. Dynamically getting height of UILabel according to Text return different Value for iOS 7.0 and iOS 6.1

Leave a Comment