Android Service学习之本地服务

public class LocalService private static final String TAG = "LocalService";

        @Override
        public IBinder onBind(Intent intent) {
                Log.i(TAG, "onBind");
                return null;
        }

        @Override
        public void onCreate() {
                Log.i(TAG, "onCreate");
                super.onCreate();
        }

        @Override
        public void onDestroy() {
                Log.i(TAG, "onDestroy");
                super.onDestroy();
        }

        @Override
        public void onStart(Intent intent, int startId) {
                Log.i(TAG, "onStart");
                super.onStart(intent, startId);
        }
}

/**
* This is an example of implementing an application service that runs locally
* in the same process as the application.    The {@link LocalServiceController}
* and {@link LocalServiceBinding} classes show how to interact with the
* service.
*
* <p>Notice the use of the {@link NotificationManager} when interesting things
* happen in the service.    This is generally how background services should
* interact with the user, rather than doing something more disruptive such as
* calling startActivity().
*/
public class LocalService extends Service {
        private NotificationManager mNM;

        /**
         * Class for clients to access.    Because we know this service always
         * runs in the same process as its clients, we don‘t need to deal with
         * IPC.
         */
public class LocalBinder extends Binder {
                return LocalService.this;
                }
        }
        
        @Override
        public void onCreate() {
                mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);

                // Display a notification about us starting.    We put an icon in the status bar.
                showNotification();
        }

        @Override
        public int onStartCommand(Intent intent, int flags, int startId) {
                Log.i("LocalService", "Received start id " + startId + ": " + intent);
                // We want this service to continue running until it is explicitly
                // stopped, so return sticky.
                return START_STICKY;
        }

        @Override
        public void onDestroy() {
                // Cancel the persistent notification.
                mNM.cancel(R.string.local_service_started);

                // Tell the user we stopped.
                Toast.makeText(this, R.string.local_service_stopped, Toast.LENGTH_SHORT).show();
        }

        @Override
        public IBinder onBind(Intent intent) {
             return mBinder;
        }

        // This is the object that receives interactions from clients.    See
        // RemoteService for a more complete example.
private final IBinder mBinder = new LocalBinder();

        /**
         * Show a notification while this service is running.
         */
        private void showNotification() {
                // In this sample, we‘ll use the same text for the ticker and the expanded notification
                CharSequence text = getText(R.string.local_service_started);

                // Set the icon, scrolling text and timestamp
                Notification notification = new Notification(R.drawable.stat_sample, text,
                                System.currentTimeMillis());

                // The PendingIntent to launch our activity if the user selects this notification
                PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
                                new Intent(this, LocalServiceController.class), 0);

                // Set the info for the views that show in the notification panel.
                notification.setLatestEventInfo(this, getText(R.string.local_service_label),
                                             text, contentIntent);

                // Send the notification.
                // We use a layout id because it is a unique number.    We use it later to cancel.
                mNM.notify(R.string.local_service_started, notification);
        }
}

/**
* <p>Example of binding and unbinding to the {@link LocalService}.
* This demonstrates the implementation of a service which the client will
* bind to, receiving an object through which it can communicate with the service.</p>
*/
public class LocalServiceBinding extends Activity {
        private boolean mIsBound;
        private LocalService mBoundService;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);

                setContentView(R.layout.local_service_binding);

                // Watch for button clicks.
                Button button = (Button)findViewById(R.id.bind);
                button.setOnClickListener(mBindListener);
                button = (Button)findViewById(R.id.unbind);
                button.setOnClickListener(mUnbindListener);
        }

private ServiceConnection mConnection = new ServiceConnection() {
                public void onServiceConnected(ComponentName className, IBinder service) {
                        // This is called when the connection with the service has been
                        // established, giving us the service object we can use to
                        // interact with the service.    Because we have bound to a explicit
                        // service that we know is running in our own process, we can
                        // cast its IBinder to a concrete class and directly access it.
                        mBoundService = ((LocalService.LocalBinder)service).getService();  
                        
                        // Tell the user about this for our demo.
                        Toast.makeText(LocalServiceBinding.this, R.string.local_service_connected,
                                        Toast.LENGTH_SHORT).show();
                }

// This is called when the connection with the service has been
                        // unexpectedly disconnected -- that is, its process crashed.
                        // Because it is running in our same process, we should never
                        // see this happen.
                        mBoundService = null;
                        Toast.makeText(LocalServiceBinding.this, R.string.local_service_disconnected,
                                        Toast.LENGTH_SHORT).show();
                }
        };

        private OnClickListener mBindListener = new OnClickListener() {
                public void onClick(View v) {
                        // Establish a connection with the service.    We use an explicit
                        // class name because we want a specific service implementation that
                        // we know will be running in our own process (and thus won‘t be
                        // supporting component replacement by other applications).
                        class), mConnection, Context.BIND_AUTO_CREATE);
                        mIsBound = true;
                }
        };

        private OnClickListener mUnbindListener = new OnClickListener() {
                public void onClick(View v) {
                        if (mIsBound) {
                                // Detach our existing connection.
                                unbindService(mConnection);
                                mIsBound = false;
                        }
                }
        };
}