Convert double value to List<Int> in Dart - flutter

Question

I'm using flutter_blue to communicate with a bluetooth device. I need to pass a double value to the bluetooth device using the flutter_blue write() method.
The value must be passed to the method as a list of integers which is supposed to represent a list of bytes as far as i understand it.
The flutter_blue write method:
Future<Null> write(
List<int> value,
{bool withoutResponse = false}
)
Is there a way to convert a double value to a list of integers that represents the double value as a list of bytes in order to pass it to flutter_blues write method?
For example:
double value = 10.52;
List<Int> convertedValue = someConversionMethod(value);
await bluetoothCharacteristic.write(convertedValue);

Answer 1

With Bluetooth it is normal to pass information as a list of bytes(Uint8List). The solution for float value is to have an expected exponent. There is more detail in the GATT Specification Supplement 4 especially in section 2 "Values and represented values"
If the number is large enough it will need to be converted to bytes in little endian format. As an example:
import 'dart:typed_data';
import 'dart:math';
void main() {
double value = 10.52;
var rawValue = value * pow(10, 2); // multiply value to remove decimal places
print('Raw value to send: $rawValue'); // Raw value to send 1052
var sendValue = ByteData(2);
sendValue.setUint16(0, rawValue.toInt(), Endian.little);
print('As Uint8List of values: ${sendValue.buffer.asUint8List()}');
// As Uint8List of values: [28, 4]
}

Answer 2

The dart:typed_data library has some useful methods to convert data to bytes. This method worked for me.
import 'dart:typed_data';
List<int> doubleToListInt(double value) {
ByteData bytes = ByteData(8);
bytes.setFloat64(0, value);
List<int> response =
bytes.buffer.asInt8List().toList();
return response;
}
print(doubleToListInt(10.52)); // Returns [64, 37, 10, 61, 112, -93, -41, 10]