BridgeCallback.java

class BridgeCallback implements IOAcknowledge, IOCallback {

	...
	@Override
	public void ack(Object... args) {
		String argsStr = TextUtils.join(",", args);
		final String callback = "javascript:" + mCallback + "(" + argsStr + ");";
		((MainActivity)mContext).runOnUiThread(new Runnable() {
			public void run() {
				mWebView.loadUrl(callback);	
			}
		});
	}
	...

client.js

if Android?
  window.socketCallbacks = {}
  window.socket = Backbone.socket = #Android.socket()
    on: (event, cb) ->
      window.socketCallbacks[event] = cb
    emit: (event, data, cb) ->
      functionName = 'cb' + Math.floor(Math.random()*100000000000000000)
      if typeof data == 'function'
        cb = data
        data = null

      window[functionName] = cb
      Android.emit event, JSON.stringify(data), "window.#{functionName}"

JavascriptInterface.java

mWebView.addJavascriptInterface(new JavaScriptInterface() {
	public void emit(String event, String data, String callback) {
		if("null".equals(data)) {
			mSocket.emit(event, new BridgeCallback(mWebView, mContext, callback));
		} else {
			Object json = null;
			try {
				json = new JSONObject(data);
			} catch (JSONException e) {
				try {
					json = new JSONArray(data);
				} catch (JSONException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				}
			}
			mSocket.emit(event, new BridgeCallback(mWebView, mContext, callback), json);
			}
	}
}, "Android");

WebView.java

mWebView.setWebViewClient(new android.webkit.WebViewClient() {
	public void onPageStarted(WebView view, String url, Bitmap favicon) {
		SocketIO socket;
		try {
			socket = new SocketIO(hostUri.toString());
		} catch (MalformedURLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		socket.connect(new IOCallback() {
			@Override
			public void onMessage(JSONObject json, IOAcknowledge ack) {
				try {
					System.out.println("Server said:" + json.toString(2));
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
			@Override
			public void onMessage(String data, IOAcknowledge ack) {
				System.out.println("Server said: " + data);
			}
			@Override
			public void onError(SocketIOException socketIOException) {
				System.out.println("an Error occured");
				socketIOException.printStackTrace();
			}
			@Override
			public void onDisconnect() {
				System.out.println("Connection terminated.");
			}
			@Override
			public void onConnect() {
				System.out.println("Connection established");
			}
			@Override
			public void on(String event, IOAcknowledge ack, Object... args) {
				new BridgeCallback(mWebView, this, "window.socketCallbacks[\"" + event + "\"]").ack(args);
					mWebView.loadUrl(callback);	
			}
		});
	}