Android 应用程序使用 Socket.io 连接到 Node.js 服务器
我无法让我的 Android 应用程序连接到 socket.io 聊天服务器.我正在使用由 Gottox 创建的 socket.io-java-client,可以在这里找到:https://github.com/Gottox/socket.io-java-client
I'm having trouble getting my Android app to connect to a socket.io chat server. I'm using socket.io-java-client created by Gottox which can be found here: https://github.com/Gottox/socket.io-java-client
服务器通过端口 7000 在本地运行.我使用的是 android 模拟器,所以我使用 10.0.2.2:7000 访问服务器.
The server runs locally over port 7000. I'm using the android emulator, so I'm using 10.0.2.2:7000 to access the server.
任何帮助将不胜感激,我对 SSL 没有太多经验.如果我找到了可行的解决方案,我也会发布.
Any help would be appreciated, I don't have much experience at all with SSL. If I find a working solution I'll also post it.
Node.js 服务器
var express = require('express');
var app = express();
var server = require('http').createServer(app).listen(7000);
var io = require('socket.io').listen(server);
io.sockets.on('connection', function(client){
client.on('message', function(err, msg){
client.broadcast.emit('message', msg);
});
});
package.json
{
"name": "simplechat",
"version": "0.0.1",
"main": "app.js",
"dependencies": {
"express" : "~4.0.0",
"socket.io" : "~0.9.13"
}
}
Android:SendMessageActivity
public class SendMessageActivity extends Activity {
private static final String SERVER_ADDRESS = "https://10.0.2.2:7000";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_send_message);
System.out.println("Sever: " + SERVER_ADDRESS);
try {
SocketIO socket = new SocketIO(new URL(SERVER_ADDRESS), new IOCallback() {
@Override
public void onDisconnect() {
System.out.println("disconnected");
}
@Override
public void onConnect() {
System.out.println("connected");
}
@Override
public void onMessage(String s, IOAcknowledge ioAcknowledge) {
}
@Override
public void onMessage(JSONObject jsonObject, IOAcknowledge ioAcknowledge) {
}
@Override
public void on(String event, IOAcknowledge ioAcknowledge, Object... objects) {
}
@Override
public void onError(SocketIOException e) {
e.printStackTrace();
}
});
} catch (MalformedURLException ex) {
ex.printStackTrace();
}
}
Android 权限
<uses-permission
android:name="android.permission.INTERNET">
</uses-permission>
错误代码
08-09 16:07:28.224 8411-8441/com.example.puma.chatexample W/System.err﹕ io.socket.SocketIOException: Error while handshaking
08-09 16:07:28.225 8411-8441/com.example.puma.chatexample W/System.err﹕ at io.socket.IOConnection.handshake(IOConnection.java:322)
08-09 16:07:28.225 8411-8441/com.example.puma.chatexample W/System.err﹕ at io.socket.IOConnection.access$600(IOConnection.java:39)
08-09 16:07:28.225 8411-8441/com.example.puma.chatexample W/System.err﹕ at io.socket.IOConnection$ConnectThread.run(IOConnection.java:199)
08-09 16:07:28.226 8411-8441/com.example.puma.chatexample W/System.err﹕ Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'javax.net.ssl.SSLSocketFactory javax.net.ssl.SSLContext.getSocketFactory()' on a null object reference
08-09 16:07:28.226 8411-8441/com.example.puma.chatexample W/System.err﹕ at io.socket.IOConnection.handshake(IOConnection.java:302)
08-09 16:07:28.227 8411-8441/com.example.puma.chatexample W/System.err﹕ ... 2 more
我确实解决了这个问题.我使用了我电脑的本地 IP http://192.168.0.xxx:7000 并且该应用程序能够连接到聊天服务器从模拟器.我不知道这为什么有效,但它可能会在未来帮助某人 :)
I actually solved the problem. I used my PC's local IP http://192.168.0.xxx:7000 and the app was able to connect to the chat server from the emulator. I don't know why this works, but it might help out someone in the future :)
更新:
这就是我最终构建项目的方式.我创建了一个单例类来处理 Android 端的套接字连接(您也可以将其作为服务来实现).接收消息时,单例类向应用程序的其余部分广播一个意图.然后意图被相关活动中的广播接收器接收.
This is how I ended up structuring the project. I created a singleton class to handle socket connections Android side (you could also do it as a service). When receiving a message, the singleton class broadcasts an intent to the rest of the app. The intent is then picked up by a broadcast receiver in the relevant activity.
Android 端(单例):
public class SocketSingleton {
private static SocketSingleton instance;
private static final String SERVER_ADDRESS = "http://1.2.3.4:1234";
private SocketIO socket;
private Context context;
public static SocketSingleton get(Context context){
if(instance == null){
instance = getSync(context);
}
instance.context = context;
return instance;
}
public static synchronized SocketSingleton getSync(Context context){
if (instance == null) {
instance = new SocketSingleton(context);
}
return instance;
}
public SocketIO getSocket(){
return this.socket;
}
private SocketSingleton(Context context){
this.context = context;
this.socket = getChatServerSocket();
this.friends = new ArrayList<Friend>();
}
private SocketIO getChatServerSocket(){
try {
SocketIO socket = new SocketIO(new URL(SERVER_ADDRESS), new IOCallback() {
@Override
public void onDisconnect() {
System.out.println("disconnected");
}
@Override
public void onConnect() {
System.out.println("connected");
}
@Override
public void on(String event, IOAcknowledge ioAcknowledge, Object... objects) {
if (event.equals("chatMessage")) {
JSONObject json = (JSONObject) objects[0];
ChatMessage chatMessage = new ChatMessage(json);
Intent intent = new Intent();
intent.setAction("newChatMessage");
intent.putExtra("chatMessage", chatMessage);
context.sendBroadcast(intent);
}
}
@Override
public void onError(SocketIOException e) {
e.printStackTrace();
}
});
return socket;
} catch (MalformedURLException ex) {
ex.printStackTrace();
}
return null;
}
}
Android 端(活动):
public class ChatActivity extends Activity {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_chat);
IntentFilter newChatMessageFilter = new IntentFilter("newChatMessage");
this.registerReceiver(new MessageReceiver(), newChatMessageFilter);
...
public class MessageReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent){
final ChatMessage chatMessage =(ChatMessage) intent.getExtras().get("chatMessage");
runOnUiThread(new Runnable() {
@Override
public void run() {
mAdapter.add(chatMessage);
mAdapter.notifyDataSetChanged();
}
});
}
}
}
服务器端:
var express = require('express');
var app = express();
var server = require('http').createServer(app).listen(1234);
var io = require('socket.io').listen(server);
io.sockets.on('connection', function(client){
console.log("client connected: " + client.id);
client.on("sendTo", function(chatMessage){
console.log("Message From: " + chatMessage.fromName);
console.log("Message To: " + chatMessage.toName);
io.sockets.socket(chatMessage.toClientID).emit("chatMessage", {"fromName" : chatMessage.fromName,
"toName" : chatMessage.toName,
"toClientID" : chatMessage.toClientID,
"msg" : chatMessage.msg});
});
});