Instance Method


Invoked when the central manager is about to be restored by the system.


optional func centralManager(_ central: CBCentralManager, willRestoreState dict: [String : Any])



The central manager providing this information.


A dictionary containing information about the central manager that was preserved by the system at the time the app was terminated. For the available keys to this dictionary, see Central Manager State Restoration Options.


For apps that opt in to the state preservation and restoration feature of Core Bluetooth, this is the first method invoked when your app is relaunched into the background to complete some Bluetooth-related task. Use this method to synchronize the state of your app with the state of the Bluetooth system.

See Also

Monitoring Changes to the Central Manager’s State

func centralManagerDidUpdateState(CBCentralManager)

Invoked when the central manager’s state is updated.


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