Flutter + Ethereum BIP39, BIP32

OKAddress.dart

import 'package:bip39/bip39.dart' as bip39;
import "package:hex/hex.dart";
import 'package:web3dart/credentials.dart';
import 'package:bip32/bip32.dart' as bip32;

abstract class OKAddressETH {  
  String generateMnemonic();  
  String getPrivateKey(String mnemonic);  
  Future<EthereumAddress> getPublicAddress(String privateKey);            
}

class OKAddress implements OKAddressETH {
 @override  
 String generateMnemonic() {
    return bip39.generateMnemonic();
 }
 @override  
 String getPrivateKey(String mnemonic) {
    final privateKey = HEX.encode(master.key);
    final root = bip32.BIP32.fromSeed(HEX.decode(seed));
    final child1 = root.derivePath("m/44'/60'/0'/0/0");
    final privateKey = HEX.encode(child1.privateKey); 
       
    return privateKey;  
 }
 @override  
 Future<EthereumAddress> getPublicAddress(String privateKey) async {
    final private = EthPrivateKey.fromHex(privateKey);
    final address = await private.extractAddress();    
    return address;  
 }
}

Great! Thanks

Thank you for this

Hi @oviniciusfeitosa, Are you creating a wallet?

@jhaymesdev Yes, I am both creating a new wallet and importing an existing one.

@jhaymesdev Yes, I am both creating a new wallet and importing an existing one.

Okay, I am building with flutter. What language are you using?

The same as you

Are you having any challenges?
I could be of help

String getPrivateKey(String mnemonic) is accepting a mnemonic variable but is never used.

Use this instead @oliverbytes

Future getPrivateKey(String mnemonic) async {
final seed = bip39.mnemonicToSeedHex(mnemonic);
final master = await ED25519_HD_KEY.getMasterKeyFromSeed(hex.decode(seed),
masterSecret: 'Bitcoin seed');
final privateKey = HEX.encode(master.key);
print('private: $privateKey');
return privateKey;
}

Thank you for this!
I used it like this.

class WalletAddress implements WalletAddressService {
  String hdPath = "m/44'/60'/0'/0";

  @override
  String generateMnemonic() {
    // TODO: use random bytes 
    return bip39.generateMnemonic();
  }

  @override
  Future<String> getPrivateKey(String mnemonic) async {
    final isValidMnemonic = bip39.validateMnemonic(mnemonic);
    if(!isValidMnemonic) {
      throw 'Invalid mnemonic';
    }

    final seed = bip39.mnemonicToSeed(mnemonic);
    final root = bip32.BIP32.fromSeed(seed);

    const first = 0;
    final firstChild = root.derivePath("$hdPath/$first");
    final privateKey = HEX.encode(firstChild.privateKey as List<int>);

    return privateKey;
  }
  
  ...