How to call methods of a Service from activity?

Question

I simply want to call methods of a local service from my activity. How can i do that ?

Answer 1

How do you call a normal Java method?

A obj = new A();
obj.method();

Service is a Java class. So how would you call a service method?

serviceObj.method();

Now the real question is how do you create a Service object?

Service serviceObj = new Service();

Definitely not.

In Android, Service is a System component that is created, destroyed and managed by Android OS.
For creating a service object you need IBinder.

This is how you can get a Service object from IBinder.

Once you have a hold of serviceObject. It will work like any normal Java object.
The above thing explained in the figure is called Binding a Service.

Binding makes possible to observe a background service from an Activity. With binding, we can communicate in both ways ie Activity<--->Service.
Prateek Yadav has already provided an excellent code snippet. You can use that.

Few things to keep in mind

• Never forget to unbind the service else you will lead to ResourceLeak.
• You can call startService(intent) and bindService(mIntent, mConnection, BIND_AUTO_CREATE) in any order. Binding and Starting a service are two independent things.