基于Android Service 生命周期的详细介绍

public class LService extends Service {
 private static final String TAG = "LService";
 @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 onStart(Intent intent, int startId) {
  Log.i(TAG, "onstart");
  super.onStart(intent, startId);
 }
 @Override
 public void onDestroy() {
  Log.i(TAG, "ondestoty");
  super.onDestroy();
 }
 @Override
 public boolean onUnbind(Intent intent) {
  Log.i(TAG, "onubind");
  return super.onUnbind(intent);
 }
 public String getSystemTime() {
  Time t = new Time();
  t.setToNow();
  return t.toString();
 }
 public class LBinder extends Binder {
  LService getService() {
   return LService.this;
  }
 }
}

<TextView
android:id="@+id/text"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="wecclome to Livingstone&apos;s bolg" />

<Button
android:id="@+id/startservice"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="startService" />

<Button
android:id="@+id/stopservice"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="stopService" />

<Button
android:id="@+id/bindservice"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="bindService" />

<Button
android:id="@+id/unbindservice"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="unbindService" />

public class MainActivity extends Activity implements OnClickListener {
 private LService mLService;
 private TextView mTextView;
 private Button startServiceButton;
 private Button stopServiceButton;
 private Button bindServiceButton;
 private Button unbindServiceButton;
 private Context mContext;
 // 这里需要用到ServiceConnection，在Context.bindService和context.unBindService()里用到
 private ServiceConnection mServiceConnection = new ServiceConnection() {
  // 当bindService时，让TextView显示LService里getSystemTime()方法的返回值
  @Override
  public void onServiceConnected(ComponentName name, IBinder service) {
   mLService = ((LService.LBinder) service).getService();
   mTextView.setText("I am from Service :" + mLService.getSystemTime());
  }
  public void onServiceDisconnected(ComponentName name) {
  }
 };
 public void setupViews() {
  mContext = MainActivity.this;
  mTextView = (TextView) findViewById(R.id.text);

  startServiceButton = (Button) findViewById(R.id.startservice);
  stopServiceButton = (Button) findViewById(R.id.stopservice);
  bindServiceButton = (Button) findViewById(R.id.bindservice);
  unbindServiceButton = (Button) findViewById(R.id.unbindservice);
  startServiceButton.setOnClickListener(this);
  stopServiceButton.setOnClickListener(this);
  bindServiceButton.setOnClickListener(this);
  unbindServiceButton.setOnClickListener(this);
 }
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  setupViews();
 }
 @Override
 public void onClick(View v) {
  if (v == startServiceButton) {
   Intent i = new Intent(MainActivity.this, LService.class);
   mContext.startService(i);
  } else if (v == stopServiceButton) {
   Intent i = new Intent(MainActivity.this, LService.class);
   mContext.stopService(i);
  } else if (v == bindServiceButton) {
   Intent i = new Intent(MainActivity.this, LService.class);
   mContext.bindService(i, mServiceConnection, BIND_AUTO_CREATE);
  } else {
   mContext.unbindService(mServiceConnection);
  }
 }
}