Tells the delegate the central manager’s state updated.
- iOS 5.0+
- macOS 10.7+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 4.0+
- Core Bluetooth
The central manager whose state has changed.
You implement this required method to ensure that the central device supports Bluetooth low energy and that it’s available to use. You should issue commands to the central manager only when the central manager’s
state indicates it’s powered on. A state with a value lower than
CBCentral implies that scanning has stopped, which in turn disconnects any previously-connected peripherals. If the state moves below
CBPeripheral objects obtained from this central manager become invalid; you must retrieve or discover these peripherals again. For a complete list of possible states, see the
CBCentral enumeration in