Android 调用 class 使用新线程连接到服务器时，应用程序崩溃

Question

这是有问题的 class

public class ServerLink {

private static Context context;
private Socket sock;
private String IP;
private int Port;
private InputStream is;
private OutputStream out;
private String temp;
private boolean bTemp;

public ServerLink(Context contxt){
    this(contxt,"18.220.103.72",2267);
}

public ServerLink(Context contxt,String inIP, int inPort){
    context = contxt;
    IP = inIP;
    Port = inPort;
}

public boolean sendLoginToServer(final String pass, final String username){
    Thread t1 = new Thread(new Runnable() {
        public void run()
        {
            try{
                bTemp = false;
                sock = new Socket(IP,Port);
                out = sock.getOutputStream();
                is = sock.getInputStream();

                sendToServer("Login");
                sendToServer(username.length() + ";" + username + ";" + pass);

                temp = "";
                String serverAnswer = Listener();

                if(serverAnswer.equals("")){
                    Toast.makeText(context,"WTF",Toast.LENGTH_LONG).show();
                }
                else if(serverAnswer.equals("login")){
                    Toast.makeText(context,"Yay",Toast.LENGTH_LONG).show();
                    bTemp = true;
                }
                else if(serverAnswer.equals("nigol")){
                    Toast.makeText(context,"Nay",Toast.LENGTH_LONG).show();
                }
            }
            catch (java.io.IOException e){
                Toast.makeText(context,e.getMessage().toString(),Toast.LENGTH_LONG).show();
            }
        }});
    t1.start();
    return bTemp;
}

public void sendToServer(String input){
    try{

        String toSend = input;
        byte[] toSendBytes = toSend.getBytes();
        int toSendLen = toSendBytes.length;
        byte[] toSendLenBytes = new byte[4];
        toSendLenBytes[0] = (byte)(toSendLen & 0xff);
        toSendLenBytes[1] = (byte)((toSendLen >> 8) & 0xff);
        toSendLenBytes[2] = (byte)((toSendLen >> 16) & 0xff);
        toSendLenBytes[3] = (byte)((toSendLen >> 24) & 0xff);
        out.write(toSendLenBytes);
        out.write(toSendBytes);

    }
    catch (java.io.IOException e){
        Toast.makeText(context,e.getMessage().toString(),Toast.LENGTH_LONG).show();
    }
}

public String Listener(){
    try {
        byte[] lenBytes = new byte[4];
        is.read(lenBytes, 0, 4);
        int len = (((lenBytes[3] & 0xff) << 24) | ((lenBytes[2] & 0xff) << 16) |
                ((lenBytes[1] & 0xff) << 8) | (lenBytes[0] & 0xff));
        byte[] receivedBytes = new byte[len];
        is.read(receivedBytes, 0, len);
        String message = new String(receivedBytes, 0, len);
        return message;
    }
    catch (java.io.IOException e){
        Toast.makeText(context,e.getMessage().toString(),Toast.LENGTH_LONG).show();
        return  e.getMessage().toString();
    }
}
}

它在调用时使我的应用程序崩溃。我尝试为每个人使用一个新线程，这段代码确实有效，我尝试将它用作方法，但它是一个小组项目，所以我想要一个 class 每个人都可以轻松使用，但目前不起作用.它应该连接到一个服务器 returns 如果成功登录，如果不成功则 nigol，服务器可以工作，我们已经在其他平台上测试过它，但我似乎无法class 正确[=13] =]

Answer 1

您无法显示来自 UI 以外的任何线程的 toast 消息。我建议使用 AsyncTask 或使用这个：

MyActivity.this.runOnUiThread(new Runnable() {
    public void run() {
        Toast.makeText(activity, "Hello", Toast.LENGTH_SHORT).show();
    }
});

Android 调用 class 使用新线程连接到服务器时，应用程序崩溃

Android app crashes when class is called that uses a new thread to connect to server

java

sockets

android

java-threads