1. Lecture 7: Android Services
By: Eliav Menachi

2. Services
Services are components that run in the background, without a user interface
Android supports two types of services:.
Local service: not accessible from other applications running on the device
Remote service: accessible from other applications in addition to the application hosting the service

3. Local Services Started via Context.startService() Runs until:
Context.stopService()
stopSelf()
See SimpleService example

4. Remote service
Service that can be consumed by other processes via Remote Procedure Call (RPC)
Android Interface Definition Language (AIDL): define the interface that will be exposed to clients

5. Building Remote service
To build a remote service, you do the following:
Write an AIDL file that defines your interface to clients
Add the AIDL file to your Eclipse project - generate a Java interface from the AIDL file
Implement the service and return the interface from the onBind() method
Add the service configuration to your AndroidManifest.xml

6. 1. Implementing AIDL
AIDL is a simple syntax that lets you declare an interface with one or more methods
The parameters and return values can be of any type, even other AIDL-generated interfaces
you must import all non-built-in types, even if they are defined in the same package as your interface

7. AIDL Data types Data types that AIDL can support:
Primitive types (int, boolean…)
String
List - the other side will receive an ArrayList
Map - the other side will receive a HashMap
CharSequence
Other AIDL-generated interfaces
Custom classes that implement the Parcelable protocol

8. 2. Generate a Java interface from AIDL
Add the AIDL file to your Eclipse project
Eclipse will automatically call the AIDL compiler and will generate the Java interface from the AIDL file

9. 3. Implementing AIDL Interface
Write a class that extends android.app.Service
Implement:
Implement the interface method
Implement the onBind() method

10. 4. Service Configuration
Add the service configuration to your AndroidManifest.xml
<service android:name=".AIDLServiceImpl">
<intent-filter>
<action android:name="bgu.eliav.AIDLServiceInterface" />
</intent-filter>
</service>

11. Calling the Service copy the AIDL file to the client project
AIDL compiler creates the interface
Extends the ServiceConnection
get a reference to the service
call the bindService()

12. Service lifecycle