Service

main Activity用来启动和关闭Service,Count是Service实现类,Manifest中加<service android:name=".Count" />

public class Main extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        startService(new Intent(this, Count.class));
    }

    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        stopService(new Intent(this, Count.class));
    }

}

public class Count extends Service {
    private boolean threadDisable;
    private int count;

    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public void onCreate() {
        // TODO Auto-generated method stub
        super.onCreate();
        Log.v("count", "onCreate");
    }

    @Override
    public void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        this.threadDisable = true;
        Log.v("count", "onDestroy");
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        // TODO Auto-generated method stub
        Log.v("count", "onStartCommand");
        new Thread(new Runnable() {

            @Override
            public void run() {
                // TODO Auto-generated method stub
                while (!threadDisable) {
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    count++;
                    Log.v("count", "Count is " + count);
                }
            }
        }).start();
        return START_STICKY;

    }

}

START_STICKY确保Service一直保持启动状态，但不能保证Intent被处理执行；START_REDLIVER_INTENT可以确保Service在意外终止后将自动重新运行并保证Intent被处理；START_NOT_STICKY在Service被意外终止后将停止运行