编辑:我想通过 Web 界面在 Android 和浏览器上实现一个测验应用程序。我正在寻找一种在服务器和客户端之间进行通信的方法。我尝试了 socket.io,但无法让它与 android 一起使用。
我正在使用托管在 nodester (nodester.com) 上的 node.js 服务器。我尝试了一些库,但无法正常工作。
我现在正在使用来自https://github.com/einaros/ws的 einaros/ws
服务器代码是:
var clients = [],
numClients = 0;
var WebSocketServer = require('ws').Server,
wss = new WebSocketServer({port: 20083});
wss.on('connection', function(ws) {
ws.on('message', function(message) {
console.log(wss.clients);
console.log('received: %s', message);
incomingMessage(message, ws)
});
/*
ws.on('eigenesEvent', function(message) {
console.log('eigenes Event ausgelöst: ' + message);
});
*/
});
function incomingMessage(msg, ws) {
//console.log(wss.clients);
var obj = JSON.parse(msg);
if(obj.type == "connect") {
for(var i=0;i<clients.length;i++) {
if(clients[i] == obj.id) {
ws.send(JSON.stringify({
to: obj.id,
message: "name vergeben"
}));
return;
}
}
clients[numClients] = obj.id;
numClients++;
for(var i=0;i<clients.length;i++) {
console.log("Client" + i + ": " + clients[i]);
}
ws.send(JSON.stringify({
to: "all",
message: obj.id + " connected"
}));
}
if(obj.type == "disconnect") {
for(var i=0;i<clients.length;i++) {
if(clients[i] == obj.id) {
clients.splice(i, 1);
numClients--;
for(var i=0;i<clients.length;i++) {
console.log("Client" + i + ": " + clients[i]);
}
}
}
ws.send(JSON.stringify({
to: "all",
message: obj.id + " disconnected"
}));
return;
}
if(obj.type == "answer") {
if("id" in obj) {
if(obj.answer == "a") {
ws.send(JSON.stringify({
to: obj.id,
message: "a is correct"
}));
} else {
ws.send(JSON.stringify({
to: obj.id,
message: "answer is incorrect"
}));
}
}
}
if(obj.type == "something") {
if("id" in obj) {
ws.send(JSON.stringify({
to: obj.id,
message: "received: " + obj.message
}));
}
}
}
从 HTML 站点,我可以通过以下方式连接到服务器:
connect = function() {
var host = "ws://einaros.nodester.com";
try{
socket = new WebSocket(host);
console.log('WebSocket - status ' + socket.readyState);
socket.onopen = function(msg) {
console.log("Welcome - status " + this.readyState);
socket.send(JSON.stringify({
id: model.getClientName(),
type: "connect"
}));
model.setConnectionStatus(true);
};
socket.onmessage = function(msg) {
console.log("onmessage - msg: " + msg.data);
checkMessage(msg.data);
};
socket.onclose = function(msg) {
console.log("Disconnected - status " + this.readyState);
model.setConnectionStatus(false);
};
}
catch(ex){
console.log(ex);
}
},
在 Android 客户端我使用 AutobahnAndroid 来自:http
://autobahn.ws/android
android 的客户端代码是:
package ps.mediengestaltung;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import de.tavendo.autobahn.WebSocketConnection;
import de.tavendo.autobahn.WebSocketException;
import de.tavendo.autobahn.WebSocketHandler;
public class MainActivity extends Activity {
public final WebSocketConnection mConnection = new WebSocketConnection();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final String wsuri = "ws://einaros.nodester.com";
try {
mConnection.connect(wsuri, new WebSocketHandler() {
@Override
public void onOpen() {
Log.d("TAG", "Status: Connected to " + wsuri);
mConnection.sendTextMessage("Hello Server!");
}
@Override
public void onTextMessage(String payload) {
Log.d("TAG", "Got echo: " + payload);
}
@Override
public void onClose(int code, String reason) {
Log.d("TAG", "Connection lost.");
}
});
} catch (WebSocketException e) {
Log.d("TAG", e.toString());
}
}
}
在 LogCat 我得到:
08-01 08:48:13.017: D/TAG(704): 状态: 连接到 ws://einaros.nodester.com
08-01 08:48:13.167: D/TAG(704):连接丢失。
我究竟做错了什么?有什么提示吗?