In this chapter, we explored the very powerful
Service component, putting it to use to execute long-running background tasks with a configurable level of concurrency.
We learned that running tasks in a
Service gives them the best possible chance of successful completion if the user exits the application, because the system avoids killing processes with active Services unless absolutely necessary.
We discovered various ways to initiate background work in a
Service, from starting the
Service with an
Intent object through to direct method invocation using local Services.
We also saw the wide range of communication mechanisms available for delivering results back to the user: direct invocation of local
Service methods; sending Messages with ...