AILD and Services

1. Android
AIDL and Services

2. Bibliography
1. Mark MURPHY, Beginning Android 2, Apress,
2010
– Capitolul 30
2. Lesson: Concurrency,
http://java.sun.com/docs/books/tutorial/ess
ential/concurrency/
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3. Contents
• Services
– Events
– Events loop
– Start/Stop
– Communication
• AIDL
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4. Services
• Android component
• Special for processing
• Runs in background
• Process
– Smaller pripority
– More stable (in time)
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5. Services Lifecycle
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6. Service Implementation
• Extends Service
– Simple service
• void onCreate ();
• void onStart (Intent intent, int startID);
• void onDestroy ();
– Using AIDL
• void onBind (Intent intent);
• void onUnbind();
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7. Service lifecycle
• Share the same thread
with activities
• Processing is not
allowed within lifecycle
functions
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8. Service implementation
1. Extend Service
– Implement functions
– Create threads
2. Declare in manifest
3. Start / stop
– startService (…)
– stopService (…)
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9. Example
• Display one prime number each second
– Service does not start automatically
– Service does not stop automatically
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10. NumerePrime - Service
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11. NumerePrime – Actual thread
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12. Start service
Intent starter = new Intent (context,
ServiceClass.class);
context.startService (starter);
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13. Stop service
context.stopService (starter);
stopSelf ();
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14. AIDL
• Android Interface
Definition Language
– RPC for Android
• Connects the activities
and services
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15. Remote Procedure Call
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16. AIDL
• Similar to Java
• Identical declaration
• Limited variable types
– primary (int, long, float, double, char, boolean)
– String
– List*
– Map*
– Special types
* Needs to contain only AIDL specific types
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17. Example… IserviciuFilme.aidl
package pdm.film;
interface IServiciuFilme
{
int numarFilme ();
String titluFilm (int numar);
String regizorFilm (int numar);
}
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18. AIDL => clasă
• IServiciuFilme.aidl
– IServiciuFilme.Stub
• Abstract class containing the functions in the Interface
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19. ListaFilme - Service
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20. ListaFilme – the actual service
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21. Connect Using AIDL
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22. Connect Using AIDL
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23. Questions
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