adapterState property

@override Stream<BluetoothAdapterState> get adapterState

实现 FlutterBluetoothPluginPlatform.adapterState。

订阅时先发送当前映射状态，随后转发浏览器 availabilitychanged 事件。

Implementation

@override
Stream<BluetoothAdapterState> get adapterState async* {
  yield await getAdapterState();
  yield* _adapterStateController.stream;
}