Service without Activity. how?

I am new to android.. just started writing service using activity.. i want to know if there are any other ways to trigger a service without the use of activity? like when a new message arrives, the service need to start running..

if 开发者_高级运维so, how?

Thank you..

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In the abstract, what you want is a manifest-registered BroadcastReceiver that then starts the service.

That being said, there is no support in the Android SDK for events fitting the description of "when a new message arrives".