Question

我的MainActivity中有一个选中的按钮。如果选中该按钮，它应该启动服务，但如果用户取消选中该按钮，我想停止该服务。

所以在取消检查条件下我写了stopService(intentname);，但问题是服务没有停止。这是我的代码片段：

服务类

public class SimpleService extends Service 
{
    String selectedAudioPath = "";
    private MyThread myythread;
    public Intent intent;
    public boolean isRunning = false;

    long interval=30000;

    @Override
    public IBinder onBind(Intent arg0) 
    {
        return null;
    }

    @Override
    public void onCreate() 
    {
        super.onCreate();
        myythread  = new MyThread(interval);
    }

    @Override
    public synchronized void onDestroy() 
    {
        super.onDestroy();

        if(!isRunning)
        {
            myythread.interrupt();
            myythread.stop();
            isRunning = false;
        }
    }

    @Override
    public synchronized void onStart(Intent intent, int startId) 
    {
        super.onStart(intent, startId);

        if(!isRunning)
        {
            //this.intent = intent;
            //System.out.println("the intent is" + intent);
            myythread.start();
            isRunning = true;
        }
    }

    class MyThread extends Thread
    {
        long interval;
        public MyThread(long interval)
        {
            this.interval=interval;
        }

        @Override
        public void run()
        {
            while(isRunning)
            {
                System.out.println("Service running");
                try 
                {
                    String myString = intent.getStringExtra("name");
                    if(myString == null)
                        Log.d("Service","null");
                    else
                    {
                        Log.d("Service","not null");
                        if(myString.equalsIgnoreCase("image"))
                        {
                            uploadImages();
                            Thread.sleep(interval);
                        }
                        else if(myString.equalsIgnoreCase("audio"))
                        {
                            uploadAudio();
                            Thread.sleep(interval);
                        }
                    }
                } 
                catch (InterruptedException e) 
                {
                    isRunning = false;
                    e.printStackTrace();
                }
            }
        }

Answer 1

您无法阻止具有此类

运行不可阻挡循环的线程

while(true)
{

}

要停止该线程，请声明一个布尔变量并在while循环条件下使用它。

public class MyService extends Service {
      ... 
      private Thread mythread;
      private boolean running;



     @Override
     public void onDestroy()
     {
         running = false;
         super.onDestroy();
     }

     @Override
     public void onStart(Intent intent, int startid) {

         running = true;
       mythread = new Thread() { 
       @Override
       public void run() {
         while(running) {
                   MY CODE TO RUN;
                 }
         }
       };
     };
     mythread.start();

}

来源：Stopping a thread inside a service

Answer 2

不要使用线程。请改用AsyncTask。

public class MyService extends Service {

    private AsyncTask<Void,Void,Void> myTask;

    @Override
    public void onDestroy(){
         super.onDestroy();
         myTask.cancel(true);
    }

    @Override
    public void onStart(Intent intent, int startid) {
        myTask = new AsyncTask<Void,Void,Void>(){
            @Override
            public void doInBackground(Void aVoid[]){
                doYourWorkHere();
            }
        }
        myTask.execute();
    }

}

android - 如何在服务中停止线程？

2 个答案: