启动多个service，如何知道哪个service是否启动

Question

final boolean ServiceAOn = (PendingIntent.getService(_context, SERVICE_A_UNIQUE_ID,
new Intent(_context, ServiceA.class),
PendingIntent.FLAG_NO_CREATE) != null);
我想知道SERVICE_A的状态，是否已经启动，但是第一次有用，第二次就没用了

            附上代码：
            package com.example.test;

import java.text.SimpleDateFormat;
import java.util.Date;

import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.ScrollView;
import android.widget.TextView;
import android.widget.Toast;

import com.example.alarmmanagertest.R;
import com.example.service.ServiceA;
import com.example.service.ServiceB;
import com.example.service.ServiceC;

public class MainActivity extends Activity {
private Context _context;
private int SERVICE_A_TIME_INTERVAL = 10;
private int SERVICE_B_TIME_INTERVAL = 20;
private int SERVICE_C_TIME_INTERVAL = 30;
private int SERVICE_A_UNIQUE_ID = 0;
private int SERVICE_B_UNIQUE_ID = 1;
private int SERVICE_C_UNIQUE_ID = 2;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    _context = this;
    setContentView(R.layout.activity_main);
    initView();
}

private void initView() {
    Button btn_start_alarm = (Button) findViewById(R.id.btn_start_alarm);
    btn_start_alarm.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            // Start all service
            fn_start_all_alarm();
        }
    });

    Button btn_stop_alarm = (Button) findViewById(R.id.btn_stop_alarm);
    btn_stop_alarm.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            fn_cancel_all_alarm();
        }
    });

    final boolean ServiceAOn = (PendingIntent.getService(_context, SERVICE_A_UNIQUE_ID,
            new Intent(_context, ServiceA.class),
            PendingIntent.FLAG_NO_CREATE) != null);
    Button btn_startOrStop_a = (Button) findViewById(R.id.btn_startOrStop_a);
    btn_startOrStop_a.setText(ServiceAOn == true ? "Stop Service A"
            : "Start Service A");
    btn_startOrStop_a.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            if (ServiceAOn == true) {
                fn_cancel_a_service();
                fn_refresh_activity();
            } else {
                fn_start_a_alarm();
                fn_refresh_activity();
            }
        }
    });

    final boolean ServiceBOn = (PendingIntent.getService(_context, SERVICE_B_UNIQUE_ID,
            new Intent(_context, ServiceB.class),
            PendingIntent.FLAG_NO_CREATE) != null);
    Button btn_startOrStop_b = (Button) findViewById(R.id.btn_startOrStop_b);
    btn_startOrStop_b.setText(ServiceBOn == true ? "Stop Service B"
            : "Start Service B");
    btn_startOrStop_b.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            if (ServiceBOn == true) {
                fn_cancel_b_service();
                fn_refresh_activity();
            } else {
                fn_start_b_alarm();
                fn_refresh_activity();
            }
        }
    });

    final boolean ServiceCOn = (PendingIntent.getService(_context, SERVICE_C_UNIQUE_ID,
            new Intent(_context, ServiceC.class),
            PendingIntent.FLAG_NO_CREATE) != null);
    Button btn_startOrStop_c = (Button) findViewById(R.id.btn_startOrStop_c);
    btn_startOrStop_c.setText(ServiceCOn == true ? "Stop Service C"
            : "Start Service C");
    btn_startOrStop_c.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            if (ServiceCOn == true) {
                fn_cancel_c_service();
                fn_refresh_activity();
            } else {
                fn_start_c_alarm();
                fn_refresh_activity();
            }
        }
    });
    return;
}

private void fn_start_all_alarm() {
    fn_start_a_alarm();
    fn_start_b_alarm();
    fn_start_c_alarm();
    fn_refresh_activity();
    return;

    /*****Please note that the 1.AlarmManager and 2.PendingIntent can reuse during setting alarm*******/
    /*long now = System.currentTimeMillis();
    AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
    PendingIntent pi = PendingIntent.getService(_context,
            SERVICE_A_UNIQUE_ID, new Intent(_context, ServiceA.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    am.setInexactRepeating(AlarmManager.RTC_WAKEUP, now,
            1000 * SERVICE_A_TIME_INTERVAL, pi);
    pi = PendingIntent.getService(_context, SERVICE_B_UNIQUE_ID,
            new Intent(_context, ServiceB.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    am.setInexactRepeating(AlarmManager.RTC_WAKEUP, now,
            1000 * SERVICE_B_TIME_INTERVAL, pi);

    pi = PendingIntent.getService(_context, SERVICE_C_UNIQUE_ID,
            new Intent(_context, ServiceC.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    am.setInexactRepeating(AlarmManager.RTC_WAKEUP, now,
            1000 * SERVICE_C_TIME_INTERVAL, pi);*/


}

private void fn_cancel_all_alarm() {
    fn_cancel_a_service();
    fn_cancel_b_service();
    fn_cancel_c_service();
    Toast.makeText(_context, "All service stopped", Toast.LENGTH_SHORT)
            .show();
    fn_refresh_activity();
    return;
}

private void fn_start_a_alarm() {
    long now = System.currentTimeMillis();
    AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
    PendingIntent pi = PendingIntent.getService(_context,
            SERVICE_A_UNIQUE_ID, new Intent(_context, ServiceA.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    am.setInexactRepeating(AlarmManager.RTC_WAKEUP, now,
            1000 * SERVICE_A_TIME_INTERVAL, pi);
    fn_write_log("A alarm start");
    return;
}

private void fn_start_b_alarm() {
    long now = System.currentTimeMillis();
    AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
    PendingIntent pi = PendingIntent.getService(_context,
            SERVICE_B_UNIQUE_ID, new Intent(_context, ServiceB.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    am.setInexactRepeating(AlarmManager.RTC_WAKEUP, now,
            1000 * SERVICE_B_TIME_INTERVAL, pi);
    fn_write_log("B alarm start");
    return;
}

private void fn_start_c_alarm() {
    long now = System.currentTimeMillis();
    AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
    PendingIntent pi = PendingIntent.getService(_context,
            SERVICE_C_UNIQUE_ID, new Intent(_context, ServiceC.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    am.setInexactRepeating(AlarmManager.RTC_WAKEUP, now,
            1000 * SERVICE_C_TIME_INTERVAL, pi);
    fn_write_log("C alarm start");
    return;
}

private void fn_refresh_activity() {
    ((Activity) _context).finish();
    Intent intent = new Intent(_context, MainActivity.class);
    ((Activity) _context).startActivity(intent);
}

private void fn_cancel_a_service() {
    AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
    PendingIntent ServiceAIntent = PendingIntent.getService(_context,
            SERVICE_A_UNIQUE_ID, new Intent(_context, ServiceA.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    alarmManager.cancel(ServiceAIntent);
    fn_write_log("A alarm stop");
    return;
}

private void fn_cancel_b_service() {
    AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
    PendingIntent ServiceBIntent = PendingIntent.getService(_context,
            SERVICE_B_UNIQUE_ID, new Intent(_context, ServiceB.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    alarmManager.cancel(ServiceBIntent);
    fn_write_log("B alarm stop");
    return;
}

private void fn_cancel_c_service() {
    AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
    PendingIntent ServiceCIntent = PendingIntent.getService(_context,
            SERVICE_C_UNIQUE_ID, new Intent(_context, ServiceC.class),
            Intent.FLAG_ACTIVITY_NEW_TASK);
    alarmManager.cancel(ServiceCIntent);
    fn_write_log("C alarm stop");
    return;
}

private void fn_write_log(String log_msg) {
    ScrollView scrollView = (ScrollView) findViewById(R.id.scrollView);

    View clone_row = getLayoutInflater().inflate(R.layout.clone_row, null);

    TextView datetime = (TextView) clone_row.findViewById(R.id.datetime);
    TextView serviceText = (TextView) clone_row.findViewById(R.id.serviceText);

    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    String currentDateandTime = sdf.format(new Date());

    datetime.setText(currentDateandTime);
    serviceText.setText(log_msg);

    LinearLayout linlin_layout = (LinearLayout) scrollView.findViewById(R.id.linlin_layout);
    linlin_layout.addView(clone_row);
    return;
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    return super.onOptionsItemSelected(item);
}

}