android服务是执行在UI主线程的。一下是代码demo:

package com.example.testservice;import android.os.Bundle;import android.app.Activity;import android.content.Intent;import android.view.Menu;public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); startService(new Intent(MainActivity.this,ServiceTest.class)); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } }

package com.example.testservice;import android.app.Service;import android.content.Intent;import android.os.Handler;import android.os.IBinder;import android.os.Looper;import android.os.Message;import android.util.Log;import android.widget.Toast;public class ServiceTest extends Service {private Handler mHandler=new Handler(){ @Override public void handleMessage(Message msg) { switch (msg.what) { case 1: new Thread(){ @Override public void run() { Log.i("服务", "第2个线程"); Looper.prepare(); for(int i=10;i<20;i++){ Toast.makeText(getApplicationContext(), i+"",0).show(); try { //Thread.sleep(1000); } catch (Exception e) { // TODO: handle exception } } mHandler.sendEmptyMessage(2); Looper.loop(); }; }.start(); break; case 2: new Thread(){ @Override public void run() { Log.i("服务", "第3个线程"); Looper.prepare(); for(int i=20;i<30;i++){ Toast.makeText(getApplicationContext(), i+"",0).show(); try { //Thread.sleep(1000); } catch (Exception e) { // TODO: handle exception } } mHandler.sendEmptyMessage(3); Looper.loop(); }; }.start(); break; case 3: onDestroy(); break; default: break; } super.handleMessage(msg); } }; public ServiceTest() { // TODO Auto-generated constructor stub } @Override public IBinder onBind(Intent intent) { // TODO Auto-generated method stub return null; } @Override public void onCreate() { Log.i("服务", "onCreate()"); super.onCreate(); new Thread(){ @Override public void run() { Log.i("服务", "第一个线程"); Looper.prepare(); for(int i=0;i<10;i++){ Toast.makeText(getApplicationContext(), i+"",0).show(); try { //Thread.sleep(1000); } catch (Exception e) { // TODO: handle exception } } mHandler.sendEmptyMessage(1); Looper.loop(); }; }.start(); } @Override public int onStartCommand(Intent intent, int flags, int startId) { Log.i("服务", "onStartCommand"); return super.onStartCommand(intent, flags, startId); } @Override public void onDestroy() { Log.i("服务", "onDestroy()"); super.onDestroy(); stopSelf(); } }

demo下载地址：http://download.csdn.net/detail/u014600432/8104521