Android - รบกวนผู้รู้หน่อยนะครับ ลองทดสอบ แล้ว App แล้วมันไม่สามารถใช้งานได้อ่าครับ ตอนทำไม่มี Error ใดๆๆ

import java.io.IOException;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
 
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
 
public class SimpleClientActivity extends Activity {
 
 private Socket client;
 private PrintWriter printwriter;
 private EditText textField;
 private Button button;
 private String messsage;
 
 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
 
  textField = (EditText) findViewById(R.id.editText1); //reference to the text field
  button = (Button) findViewById(R.id.button1);   //reference to the send button
 
  //Button press event listener
  button.setOnClickListener(new View.OnClickListener() {
 
   public void onClick(View v) {
 
    messsage = textField.getText().toString(); //get the text message on the text field
    textField.setText("");      //Reset the text field to blank
 
    try {
 
     client = new Socket("192.168.43.112", 4444);  //connect to server
     printwriter = new PrintWriter(client.getOutputStream(),true);
     printwriter.write(messsage);  //write the message to output stream
 
     printwriter.flush();
     printwriter.close();
     client.close();   //closing the connection
 
    } catch (UnknownHostException e) {
     e.printStackTrace();
    } catch (IOException e) {
     e.printStackTrace();
    }
   }
  });
 
 }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".SimpleClientActivity" >

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="32dp"
        android:ems="10" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="34dp"
        android:text="Send" />

</RelativeLayout>

<uses-permission android:name="android.permission.INTERNET"></uses-permission>

import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;
 
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.ServerSocket;
import java.net.Socket;
 
public class Main {
 
    private static ServerSocket serverSocket;
    private static Socket clientSocket;
    private static InputStreamReader inputStreamReader;
    private static BufferedReader bufferedReader;
    private static String message;
 
    public static void main(String[] args) {
 
        try {
            serverSocket = new ServerSocket(4444);  //Server socket
 
        } catch (IOException e) {
            System.out.println("Could not listen on port: 4444");
        }
 
        System.out.println("Server started. Listening to the port 4444");
 
        while (true) {
            try {
 
                clientSocket = serverSocket.accept();   //accept the client connection
                inputStreamReader = new InputStreamReader(clientSocket.getInputStream());
                bufferedReader = new BufferedReader(inputStreamReader); //get the client message
                message = bufferedReader.readLine();
 
                System.out.println(message);
                inputStreamReader.close();
                clientSocket.close();
 
            } catch (IOException ex) {
                System.out.println("Problem in message reading");
            }
        }
 
    }
}