Service和IntentService区别

Service简介：Android四大组件之一，运行在后台，没有界面，因为运行在主线程中，所以不能在其中做耗时操作，回阻塞UI，解决办法是新起Thread线程，处理耗时操作

IntentService简介：继承至Service用来处理异步请求，并且在所有任务完成后会主动关闭服务

测试：

service:

package com.example.administrator.intentservice;

import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.support.annotation.Nullable;

/**
 * Created by Administrator on 2015/10/20.
 */
public class MyService extends Service {
    @Override
    public void onStart(Intent intent, int startId) {
//        new Thread(new Runnable() {
//            @Override
//            public void run() {
//
//                    Thread.sleep(3 * 1000);
//                    System.out.println("Service ok");
//                } catch (InterruptedException e) {
//                    e.printStackTrace();
//                }
//            }
//        }).start();
        try {
            Thread.sleep(3 * 1000);
            System.out.println("Service ok");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        super.onStart(intent, startId);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        return super.onStartCommand(intent, flags, startId);
    }

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

IntentService:

package com.example.administrator.intentservice;

import android.app.IntentService;
import android.content.Intent;

/**
 * Created by Administrator on 2015/10/20.
 */
public class MyIntentService extends IntentService {


    public  MyIntentService(){
        super("");
    }
    /**
     * Creates an IntentService.  Invoked by your subclass's constructor.
     *
     * @param name Used to name the worker thread, important only for debugging.
     */
    public MyIntentService(String name) {
        super(name);
    }


    @Override
    protected void onHandleIntent(Intent intent) {
        try {
            Thread.sleep(3*1000);
            System.out.println("IntentService ok");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

    }
}

Manifest:

  <service android:name=".MyService"></service>
        <service android:name=".MyIntentService"></service>

测试：

package com.example.administrator.intentservice;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
//        startService(new Intent(this, MyIntentService.class));
//        startService(new Intent(this, MyIntentService.class));
//        startService(new Intent(this, MyIntentService.class));
        startService(new Intent(this, MyService.class));
        startService(new Intent(this, MyService.class));
        startService(new Intent(this, MyService.class));
    }
}

分别开启三个任务，结果如下：

IntentService:

Service:

 可见IntentService会主动创建线程去一次执行任务，而Service不开启新线程的情况下会阻塞UI线程！

参考：http://blog.youkuaiyun.com/lmj623565791/article/details/47143563