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Method: readCharacteristic

Description​

Reads the value of a specified Bluetooth characteristic.

This method asynchronously fetches the value of a specified Bluetooth characteristic from a connected device and returns it as a [BleCharacteristicValue] instance.

The method will throw a [TimeoutException] if it does not receive a response within the specified [timeout]. This safeguards against situations where the asynchronous operation hangs indefinitely.

Note: A [TimeoutException] does not necessarily indicate a failure in reading the characteristic, but rather that a response was not received in the given timeframe. Ensure that the timeout value is appropriate for the expected device response times and consider retrying the operation if necessary.

  • address: The MAC address of the Bluetooth device. This uniquely identifies the device and is used to fetch the associated BluetoothGatt instance.
  • characteristicUuid: The UUID of the characteristic whose value is to be read. This UUID should match one of the characteristics available on the connected Bluetooth device.
  • timeout: The maximum amount of time this function will wait for a response from the platform side. If this duration is exceeded without receiving a response, a [TimeoutException] will be thrown. Ensure that this duration accounts for potential delays in device communication.

Returns a Future<BleCharacteristicValue> that completes with the characteristic value once it has been read.

Example usage:

try {
  BleCharacteristicValue characteristicValue = await readCharacteristic(
    address: '00:1A:7D:DA:71:13',
    characteristicUuid: '00002a00-0000-1000-8000-00805f9b34fb',
    timeout: Duration(seconds: 10),
  );
  print(characteristicValue.value);
} catch (e) {
  print('Failed to read characteristic: $e');
}

Return Type​

Future<BleCharacteristicValue>

Parameters​

  • ``: dynamic
  • ``: dynamic