Android 如何在更改活动之前检查套接字是否已建立

每当我运行代码时，当我的套接字连接建立时，我不会被重定向到下一个活动，相反，它会移动到else部分，并显示连接失败toast。我知道它连接正确，从我的其他设备的输出。我的IF状况有问题吗？或者“Socket！=null”使用不正确

public void connecttoserver(View view){
    final TextView txtenterlumens;
    txtenterlumens = (TextView) findViewById(R.id.txtenterlumens);

    if(!txtenterlumens.getText().toString().equals("")) {
        enterlumens = Integer.parseInt(txtenterlumens.getText().toString());
        new Thread(new ClientThread()).start();
        if(socket!=null){
            Intent goToNextActivity = new Intent(getApplicationContext(), MainActivity.class);
            startActivity(goToNextActivity);
        }
        else {
            Toast.makeText(LoginActivity.this, "Fail to connect!", Toast.LENGTH_LONG).show();
            txtenterlumens.setText("");
        }

    }
    else{
        Toast.makeText(LoginActivity.this, "Please enter correct Lumens!", Toast.LENGTH_LONG).show();
        txtenterlumens.setText("");
    }


}

这是我的套接字创建代码：

public class ClientThread implements Runnable {

    @Override
    public void run() {
        try {
            InetAddress serverAddr = InetAddress.getByName(SERVER_IP);
            socket = new Socket(serverAddr, SERVERPORT);
            setSocket(socket);

        } catch (UnknownHostException e1) {
            e1.printStackTrace();

        } catch (IOException e1) {
            e1.printStackTrace();
        }
    }
}

---

您正在

ClientThread

中创建套接字，但在另一个类中验证它，但无法检索它。将此方法添加到

ClientThread

：

public boolean isConnected(){
    return socket !=null
}

然后稍微编辑您的

连接到服务器

：

ClientThread ct = new new ClientThread();
new Thread(ct).start();
        if(ct.isConnected(){...}

---

您在另一个线程上初始化套接字，因此无法立即获得结果。让我们做下面这样的事情。我还没有测试这段代码

public void connecttoserver(View view){
    final TextView txtenterlumens;
    txtenterlumens = (TextView) findViewById(R.id.txtenterlumens);

    if(!txtenterlumens.getText().toString().equals("")) {
        enterlumens = Integer.parseInt(txtenterlumens.getText().toString());
        new Thread(new ClientThread(new EstablishListener() {
            public void onEstablishCompleted(Socket socket) {
                setSocket(socket);
                if(socket!=null){
                    Intent goToNextActivity = new Intent(getApplicationContext(), MainActivity.class);
                    startActivity(goToNextActivity);
                }
                else {
                    Toast.makeText(LoginActivity.this, "Fail to connect!", Toast.LENGTH_LONG).show();
                    txtenterlumens.setText("");
                }

            }
        })).start();
    }
    else{
        Toast.makeText(LoginActivity.this, "Please enter correct Lumens!", Toast.LENGTH_LONG).show();
        txtenterlumens.setText("");
    }


}

public class ClientThread implements Runnable {
    EstablishListener mListener = null;
    public ClientThread(EstablishListener listner) {
        mListener = listner;
    }
    @Override
    public void run() {
        try {
            InetAddress serverAddr = InetAddress.getByName(SERVER_IP);
            socket = new Socket(serverAddr, SERVERPORT);
            mListener.onEstablishCompleted(socket);

        } catch (UnknownHostException e1) {
            mListener.onEstablishCompleted(null);
            e1.printStackTrace();

        } catch (IOException e1) {
            mListener.onEstablishCompleted(null);
            e1.printStackTrace();
        }
    }
}

// Create function interface for callback
public interface EstablishListener {
    void onEstablishCompleted(Socket socket);
}

---

谢谢大家的帮助。我决定，如果我在ClientThread中检查套接字连接和活动更改，这将是最简单的

 public class ClientThread implements Runnable {

    @Override
    public void run() {
        try {
            InetAddress serverAddr = InetAddress.getByName(SERVER_IP);
            socket = new Socket(serverAddr, SERVERPORT);
            setSocket(socket);
            if(socket!=null){
                Intent goToNextActivity = new Intent(getApplicationContext(), MainActivity.class);
                startActivity(goToNextActivity);
            }

        } catch (UnknownHostException e1) {
            e1.printStackTrace();

        } catch (IOException e1) {
            e1.printStackTrace();
        }
    }

}

---

您没有在

connecttoserver

中设置套接字，这就是为什么它总是为空。您可以发布包含connecttoserver（）方法的整个类文件吗？@JozefDochan我已经用这行代码设置了套接字。新线程（新ClientThread（））.start（）；哦，我现在明白了。但即使使用你的方法，我仍然会遇到同样的问题。即使新活动成功连接，我也不会被引导到该活动