java.lang.NumberFormatException: Invalid int: “” in android, server and port

Question

i'm new in Android. I have the following code:

    public class SettingsActivity extends Activity {

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.tcp_settings);

    Button buttonConnect = (Button) findViewById(R.id.buttonConnect);
    buttonConnect.setOnClickListener(new View.OnClickListener() {

        EditText server_ip = (EditText) findViewById(R.id.set_server_ip);
        EditText port = (EditText) findViewById(R.id.set_port);


        @Override
        public void onClick(View view) {

            String serverAddr = server_ip.getText().toString();
            String serverPort = port.getText().toString();

            new connectTask().execute(serverAddr, serverPort);
        }
    });
}

class connectTask extends AsyncTask<String, Void, String> {

    Socket socket;

    @Override
    protected String doInBackground(String... params) {


        int servport = Integer.parseInt(params[1]);

        try {
            socket = new Socket(params[0], servport);

        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return params[0] + " : " + params[1];
    }
}
}

I want to set a socket with server ip and port getting from EditTexts server_ip and port. In the connectTask I make a conversion from string to int in: int servport but i'm still getting error:

    Caused by: java.lang.NumberFormatException: Invalid int "".

i have to make serverAddr to String because i have to put it in :

    new connectTask().execute(serverAddr, serverPort);

But then socket require port as Int so conversion is required.

Could You help me and tell what i'm doing wrong ?

Answer 1

Your problem lies here within your code. You are passing in multiple parameters into a function that only receives one. Here is the def of execute: execute (Params... params)

new connectTask().execute(serverAddr, serverPort);

Change line to this:

new connectTask().execute(new String[]{serverAddr,serverPort});

Although the documentation does not say it, it is wanting an array of the first template object being passed in IF you are passing in more than one parameter.