WalletService does not save the mnemonic nor the private key. If you generate a new mnemonic make sure to save it!
At this point you can already use myWallet to get your address, send transactions or view your balance (which will be 0 as it is a newly created wallet!).
Import a wallet from an existing mnemonic
If you already have your mnemonic you will not need to generate a new one. You can import the wallet as follows:
Synchronizing is very important to view what your wallet has. There are some related functionalities with synchronizing such as saving the wallet state and having callbacks each time a wallet synchronizes.
Importing and creating multiple wallets
To create multiple testnet or mainnet wallets you just need one ConnectionService for each network. For example: