Question

I use Socket to connect to my local server:

public static Socket clientSocket;
public static DataOutputStream outToServer;
public static DataInputStream inToServer;

…

clientSocket = new Socket("192.168.1.102", 15780);
outToServer = new DataOutputStream(clientSocket.getOutputStream());
inToServer = new DataInputStream(clientSocket.getInputStream());
outToServer.writeBytes(nameStr + "\n");
outToServer.flush();

it works
but if I check username and go to next Activity

Intent i = new Intent(this, RoomClass.class);
startActivity(i);

i can’t use (connection is always open)

outToServer = new DataOutputStream(Connection03Activity.clientSocket.getOutputStream());
inToServer = new DataInputStream(Connection03Activity.clientSocket.getInputStream());

outToServer.writeBytes(str + "\n");
outToServer.flush();

why? how to organize connection rigth?

Answer 1

I suppose you should not try to create new In and Out streams – it was declared and initialized in first activity. Just call Connection03Activity.clientSocket.getOutputStream().writeBytes(...).

Offtopic:

Don’t forget to close streams and socket on application close – it will save battery life and traffic.