public class MainActivity extends AppCompatActivity { private EditText ipEditText; private EditText portEditText; private TextView messageTextView; private BufferedReader in; private PrintWriter out; private Socket socket; private Handler handler = new Handler(); @SuppressLint("MissingInflatedId") @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ipEditText = findViewById(R.id.ipEditText); portEditText = findViewById(R.id.portEditText); messageTextView = findViewById(R.id.messageTextView); Button connectButton = findViewById(R.id.connectButton); connectButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String ip = ipEditText.getText().toString(); int port = Integer.parseInt(portEditText.getText().toString()); new Thread(new Runnable() { @Override public void run() { try { socket = new Socket(ip, port); in = new BufferedReader(new InputStreamReader(socket.getInputStream())); out = new PrintWriter(socket.getOutputStream(), true); // 在主页面中的窗口中实时显示消息 while (true) { String message = in.readLine(); if (message == null) { break; } handler.post(new Runnable() { @Override public void run() { messageTextView.append(message + "\n"); } }); } } catch (UnknownHostException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } }).start(); } }); Button sendMessageButton = findViewById(R.id.sendMessageButton); sendMessageButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { showSendMessageDialog(); } }); } @Override protected void onDestroy() { super.onDestroy(); try { if (in != null) { in.close(); } if (out != null) { out.close(); } if (socket != null) { socket.close(); } } catch (IOException e) { e.printStackTrace(); } } private void showSendMessageDialog() { AlertDialog.Builder builder = new AlertDialog.Builder(this); LayoutInflater inflater = getLayoutInflater(); View view = inflater.inflate(R.layout.dialog_send_message, null); final EditText messageEditText = view.findViewById(R.id.messageEditText); builder.setView(view) .setTitle("发送消息") .setPositiveButton("发送", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { String message = messageEditText.getText().toString(); if (out != null) { out.println(message); } } }) .setNegativeButton("取消", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { dialog.cancel(); } }) .create() .show(); } }能帮我将这段代码中的发送信息从主线程改成子线程吗

您好，以下是将发送信息从主线程中改为子线程的代码：

sendMessageButton.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        showSendMessageDialog();
    }
});

private void showSendMessageDialog() {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    LayoutInflater inflater = getLayoutInflater();
    View view = inflater.inflate(R.layout.dialog_send_message, null);
    final EditText messageEditText = view.findViewById(R.id.messageEditText);
    builder.setView(view)
            .setTitle("发送消息")
            .setPositiveButton("发送", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    String message = messageEditText.getText().toString();
                    if (out != null) {
                        new Thread(new Runnable() {
                            @Override
                            public void run() {
                                out.println(message);
                            }
                        }).start();
                    }
                }
            })
            .setNegativeButton("取消", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            })
            .create()
            .show();
}

在这个改动中，我们将发送消息的操作放到了一个新的子线程中，防止阻塞主线程。