所以基本上它的作用是有一个显示器，其中包含一个带有用户ID的editText，两个按钮：连接和断开连接，以及反映该状态的文本视图。目前发生的事情是用户可以输入他们的ID并连接并从他们连接的服务器接收消息，但随后连接就会丢失。
MainActivity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import org.json.JSONException;
import org.json.JSONObject;
import java.net.MalformedURLException;
import java.net.URL;
import io.socket.IOAcknowledge;
import io.socket.IOCallback;
import io.socket.SocketIO;
import io.socket.SocketIOException;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private static final String SERVER_ADDRESS = "";
TextView textView_state;
EditText editText_ID;
Button button_connect;
Button button_disconnect;
SocketIO socket;
public String getUserID() {
String string = editText_ID.getText().toString();
if (string.length() > 0) {
return string;
}
else {
return null;
}
}
public JSONObject packageClient (String s) throws JSONException {
if (s != null) {
JSONObject obj = new JSONObject();
obj.put("client",s);
return obj;
}
else {
return null;
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
editText_ID = (EditText) findViewById(R.id.editText_ID);
textView_state = (TextView) findViewById(R.id.textView_state);
button_connect = (Button) findViewById(R.id.button_connect);
button_disconnect = (Button) findViewById(R.id.button_disconnect);
button_connect.setOnClickListener(this);
button_disconnect.setOnClickListener(this);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onClick(View v) {
final String client = getUserID();
if (client != null) {
switch (v.getId()) {
case R.id.button_connect:
try {
socket = new SocketIO(new URL(SERVER_ADDRESS));
socket.connect(new IOCallback() {
@Override
public void onDisconnect() {
System.out.println("Connection terminated, from connect button.");
}
@Override
public void onConnect() {
System.out.println("Connection established");
try {
JSONObject data = packageClient(client);
socket.emit("create_user_room", data);
} catch (JSONException e) {
e.printStackTrace();
}
}
@Override
public void onMessage(String s, IOAcknowledge ioAcknowledge) {
}
@Override
public void onMessage(JSONObject jsonObject, IOAcknowledge ioAcknowledge) {
}
@Override
public void on(String s, IOAcknowledge ioAcknowledge, Object... objects) {
if ("client_connected".equals(s)) {
textView_state.setText("Connected");
}
if ("client_disconnected".equals(s)) {
textView_state.setText("Disconnected");
}
}
@Override
public void onError(SocketIOException e) {
}
});
} catch (MalformedURLException e) {
e.printStackTrace();
}
break;
case R.id.button_disconnect:
try {
JSONObject data = packageClient(client);
socket.emit("request_disconnect", data);
} catch (JSONException e) {
e.printStackTrace();
}
break;
}
}
}
}
在我的android sdk上我得到了这个输出：
08-18 17:37:49.400 22449-22518/I/io.socket﹕ < 1::
08-18 17:37:49.402 22449-22518/I/io.socket﹕ > 1::/lobby:
08-18 17:37:49.414 22449-22518/I/io.socket﹕ < 1::/lobby
08-18 17:37:49.415 22449-22518/I/System.out﹕ Connection established
08-18 17:37:49.415 22449-22518/I/io.socket﹕ > 5::/lobby:{"name":"create_user_room","args":[{"client":"121"}]}
08-18 17:37:49.431 22449-22518/I/io.socket﹕ < 5::/lobby:{"args": [], "name": "client_connected"}
08-18 17:37:49.434 22449-22518/I/io.socket﹕ Cleanup
在我的服务器上，我得到了这个输出：
2015-08-18 17:38:05,281 - INFO | Client connected
2015-08-18 17:38:05,297 - INFO | Creating room for 121
2015-08-18 17:38:05,298 - INFO | Room 121 created for 121
2015-08-18 17:38:30,222 - INFO | Client disconnected
[两个不同的物理机器之间可能会有轻微的时间断开连接]
我认为它正在围绕着＃34; Cleanup＆＃34;命令，我认为它可能与通过按钮调用连接的方式有关。当我将 case R.id.button_connect：下的所有内容移动到 protected void onCreate（Bundle savedInstanceState）时，一切仍然有效，并且连接停留并按下断开连接按钮会断开用户连接：
08-18 18:08:07.816 2011-2011/I/io.socket﹕ > 5::/lobby:{"name":"request_disconnect","args":[{"client":"121"}]}
08-18 18:08:07.827 2011-2043/I/io.socket﹕ < 5::/lobby:{"args": [], "name": "client_disconnected"}
08-18 18:08:07.828 2011-2043/I/io.socket﹕ Cleanup
08-18 18:08:07.829 2011-2043/I/io.socket﹕ < 0::/lobby
08-18 18:08:07.829 2011-2043/I/io.socket﹕ Cleanup
它说了两次，不知道为什么。有谁知道我如何正确设置并调用这段代码，以便它可以解决我的连接按钮？