TCP Socket使用Android服务。(TCP Socket using Android service. how can i declare stream objects in MainActivity)

 我使用Android服务创建了一个TCP套接字连接。 在MainActivity中单击按钮时，活动开始。 并且它可以正常工作并在Activity被销毁时关闭连接。 MyService.java 
 
public class MyService extends Service{
    public static Socket clientsocket;
    public static PrintWriter printer;
    SendMessage sender;

    @Override
    public void onCreate() {
    Toast.makeText(this, "Created", Toast.LENGTH_LONG).show();
    super.onCreate();
    }

    @Override
    public void onDestroy() {
    Toast.makeText(this, "Stoped", Toast.LENGTH_LONG).show();
    if(clientsocket!=null){
            try{
            clientsocket.close(); 
            Toast.makeText(this, "Socket Closed", Toast.LENGTH_LONG).show();
            }catch(IOException e){
                e.printStackTrace();
            }
        }
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Toast.makeText(this, "Running", Toast.LENGTH_LONG).show();
        SendMessage sender=new SendMessage();
        sender.execute();
        return super.onStartCommand(intent, flags, startId);
    }

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

    class SendMessage extends AsyncTask<Void, Void, Void>{

        @Override
        protected Void doInBackground(Void... params) {
            try {
                clientsocket = new Socket("192.168.237.1", 6666);
            } catch (UnknownHostException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            if(clientsocket!=null){
                Toast.makeText(MyService.this, "Connected", Toast.LENGTH_LONG).show();
            }else{
                Toast.makeText(MyService.this, "Lost Connection", Toast.LENGTH_LONG).show();
            }
            super.onPostExecute(result);
        }

    }
}
 
 MainActivity.java 
 
public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }

    public void start(View v){
        startService(new Intent(this,MyService.class));
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.main, menu);
         return true;
    }

    class PrintMessage extends AsyncTask<Void, Void, Void>{

        @Override
        protected Void doInBackground(Void... arg0) {
            return null;
        }
    }

    @Override
    protected void onDestroy() {
        stopService(new Intent(this,MyService.class));
        super.onDestroy();
    } 
}
 
 现在我有一些问题： 
 
 
 
 是否可以使用服务的Socket对象（ clientsocket ）在MainActivity中创建PrintWriter对象？ 
 
 
 是否可以将值从MainActivity传递到服务（即IP地址和端口）？ 
 
 
 是否可以检查MainActivity中的套接字连接（即socket.isConnected ）？ 
 
 
 请帮忙 。 

I have created a TCP socket connection using Android service. The activity starts when the button is clicked in the MainActivity. And it works properly and closes the connection when the Activity is destroyed. MyService.java
 
public class MyService extends Service{
    public static Socket clientsocket;
    public static PrintWriter printer;
    SendMessage sender;

    @Override
    public void onCreate() {
    Toast.makeText(this, "Created", Toast.LENGTH_LONG).show();
    super.onCreate();
    }

    @Override
    public void onDestroy() {
    Toast.makeText(this, "Stoped", Toast.LENGTH_LONG).show();
    if(clientsocket!=null){
            try{
            clientsocket.close(); 
            Toast.makeText(this, "Socket Closed", Toast.LENGTH_LONG).show();
            }catch(IOException e){
                e.printStackTrace();
            }
        }
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Toast.makeText(this, "Running", Toast.LENGTH_LONG).show();
        SendMessage sender=new SendMessage();
        sender.execute();
        return super.onStartCommand(intent, flags, startId);
    }

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

    class SendMessage extends AsyncTask<Void, Void, Void>{

        @Override
        protected Void doInBackground(Void... params) {
            try {
                clientsocket = new Socket("192.168.237.1", 6666);
            } catch (UnknownHostException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            if(clientsocket!=null){
                Toast.makeText(MyService.this, "Connected", Toast.LENGTH_LONG).show();
            }else{
                Toast.makeText(MyService.this, "Lost Connection", Toast.LENGTH_LONG).show();
            }
            super.onPostExecute(result);
        }

    }
}
 
MainActivity.java
 
public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }

    public void start(View v){
        startService(new Intent(this,MyService.class));
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.main, menu);
         return true;
    }

    class PrintMessage extends AsyncTask<Void, Void, Void>{

        @Override
        protected Void doInBackground(Void... arg0) {
            return null;
        }
    }

    @Override
    protected void onDestroy() {
        stopService(new Intent(this,MyService.class));
        super.onDestroy();
    } 
}
 
Now I have some questions:
 
 
 
Is it possible to create PrintWriter objects in MainActivity using Socket object (clientsocket) of service?
 
 
Is it possible to pass values from MainActivity to service(i.e is IP address and port)?
 
 
Is it possible to check socket connection in MainActivity(i.e socket.isConnected)?
 
 
Please help . 

原文：https://stackoverflow.com/questions/27416952