Intent Service

An intent service allows you to run process in the background. The line <service android:name=".MyIntentService" /> must be added to your AndroidManifest.xml file. Notice that all intent services run sequentially. In my example, if you click the button twice, the second message will still came up 5 seconds after the first message. Also, intent services between different apps does NOT run sequentially. Each app runs its own intent services.

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