Event-based architecture
The wallet architecture for both the wallet implementation and the underlying UtxoProcessor is event-driven. This means you are meant to affect the wallet subsystem by registering addresses for monitoring and submitting transactions and the wallet will post appropriate transaction-related notification events and balance updates.
Wallet SDK Events
UtxoProcessor.addEventListener() function provides a way to register event listeners that receive events posted by the wallet. These include standard events such as RPC connection and disconnection events as well as transaction-related events.
The full list of events posted by UtxoProcessor can be found here: