Android™ Application Development - Bahar Ali Khan

Chapter 11: Advanced Android Development
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}
};
String link = c.getString(EarthquakeProvider.LINK_COLUMN);
double magnitude = c.getDouble(EarthquakeProvider.MAGNITUDE_COLUMN);
long datems = c.getLong(EarthquakeProvider.DATE_COLUMN);
Date date = new Date(datems);
result.add(new Quake(date, details, location, magnitude, link));
} while(c.moveToNext());
return result;
There are several considerations when implementing these methods:
❑
❑
All exceptions will remain local to the implementing process; they will not be propagated to the
calling application.
All IPC calls are synchronous. If you know that the process is likely to be time-consuming, you
should consider wrapping the synchronous call in an asynchronous wrapper or moving the
processing on the receiver side onto a background thread.
With the functionality implemented, you need to expose this interface to client applications. Expose the
IPC-enabled Service interface by overriding the onBind method within our service implementation to
return an instance of the interface.
The code snippet below demonstrates the onBind implementation for the EarthquakeService:
@Override
public IBinder onBind(Intent intent) {
return myEarthquakeServiceStub;
}
To use the IPC Service from within an Activity, you must bind it as shown in the following code snippet
taken from the Earthquake Activity:
IEarthquakeService earthquakeService = null;
private void bindService() {
bindService(new Intent(IEarthquakeService.class.getName()),
serviceConnection, Context.BIND_AUTO_CREATE);
}
private ServiceConnection serviceConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className,
IBinder service) {
earthquakeService = IEarthquakeService.Stub.asInterface(service);
}
public void onServiceDisconnected(ComponentName className) {