add ChatApplication class to keep a global socket

app/src/main/AndroidManifest.xml

@@ -6,6 +6,7 @@
 
     <application
         android:allowBackup="true"
+        android:name="com.github.nkzawa.socketio.androidchat.ChatApplication"
         android:icon="@drawable/ic_launcher"
         android:label="@string/app_name"
         android:theme="@style/AppTheme" >

app/src/main/java/com/github/nkzawa/socketio/androidchat/ChatApplication.java

@@ -0,0 +1,23 @@
+package com.github.nkzawa.socketio.androidchat;
+
+import android.app.Application;
+import io.socket.client.IO;
+import io.socket.client.Socket;
+
+import java.net.URISyntaxException;
+
+public class ChatApplication extends Application {
+
+    private Socket mSocket;
+    {
+        try {
+            mSocket = IO.socket(Constants.CHAT_SERVER_URL);
+        } catch (URISyntaxException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public Socket getSocket() {
+        return mSocket;
+    }
+}

app/src/main/java/com/github/nkzawa/socketio/androidchat/LoginActivity.java

@@ -11,14 +11,11 @@
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.TextView;
-import io.socket.emitter.Emitter;
-import io.socket.client.IO;
 import io.socket.client.Socket;
+import io.socket.emitter.Emitter;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import java.net.URISyntaxException;
-
 
 /**
  * A login screen that offers login via username.
@@ -30,19 +27,15 @@ public class LoginActivity extends Activity {
     private String mUsername;
 
     private Socket mSocket;
-    {
-        try {
-            mSocket = IO.socket(Constants.CHAT_SERVER_URL);
-        } catch (URISyntaxException e) {
-            throw new RuntimeException(e);
-        }
-    }
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_login);
 
+        ChatApplication app = (ChatApplication) getApplication();
+        mSocket = app.getSocket();
+
         // Set up the login form.
         mUsernameView = (EditText) findViewById(R.id.username_input);
         mUsernameView.setOnEditorActionListener(new TextView.OnEditorActionListener() {

app/src/main/java/com/github/nkzawa/socketio/androidchat/MainFragment.java

@@ -10,19 +10,23 @@
 import android.text.Editable;
 import android.text.TextUtils;
 import android.text.TextWatcher;
-import android.view.*;
+import android.view.KeyEvent;
+import android.view.LayoutInflater;
+import android.view.Menu;
+import android.view.MenuInflater;
+import android.view.MenuItem;
+import android.view.View;
+import android.view.ViewGroup;
 import android.view.inputmethod.EditorInfo;
 import android.widget.EditText;
 import android.widget.ImageButton;
 import android.widget.TextView;
 import android.widget.Toast;
-import io.socket.emitter.Emitter;
-import io.socket.client.IO;
 import io.socket.client.Socket;
+import io.socket.emitter.Emitter;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import java.net.URISyntaxException;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -44,13 +48,6 @@ public class MainFragment extends Fragment {
     private Handler mTypingHandler = new Handler();
     private String mUsername;
     private Socket mSocket;
-    {
-        try {
-            mSocket = IO.socket(Constants.CHAT_SERVER_URL);
-        } catch (URISyntaxException e) {
-            throw new RuntimeException(e);
-        }
-    }
 
     public MainFragment() {
         super();
@@ -68,6 +65,8 @@ public void onCreate(Bundle savedInstanceState) {
 
         setHasOptionsMenu(true);
 
+        ChatApplication app = (ChatApplication) getActivity().getApplication();
+        mSocket = app.getSocket();
         mSocket.on(Socket.EVENT_CONNECT_ERROR, onConnectError);
         mSocket.on(Socket.EVENT_CONNECT_TIMEOUT, onConnectError);
         mSocket.on("new message", onNewMessage);