android - 在 Android : Crash/Hung Issue 中设置 Signal R

Question

我按照 THIS tutorial 为我的 Android 应用程序设置了一个 .NET 后端来实现 Signal R。我设置了一个 SignalR 自托管后端。

这是我在控制台项目中的后端代码:

namespace SignalRSelfHost
{
    class Program
    {
        static void Main(string[] args)
        {
            // This will *ONLY* bind to localhost, if you want to bind to all addresses
            // use http://*:8080 to bind to all addresses. 
            // See http://msdn.microsoft.com/en-us/library/system.net.httplistener.aspx 
            // for more information.
            string url = "http://localhost:8080";
            using (WebApp.Start(url))
            {
                Console.WriteLine("Server running on {0}", url);
                Console.ReadLine();
            }
        }
    }
    class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            app.UseCors(CorsOptions.AllowAll);
            app.MapSignalR();
        }
    }
    public class MessageHub : Hub
    {
        public static event Action<string, string> MessageReceived = delegate { };

        public void SendMessage(string name, string message)
        {
            MessageReceived(name, message);
        }

    }

    public class CustomType
    {
        public string Name;
        public int Id;
    }
}

我的安卓代码:

    Handler handler;
    TextView statusField;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        handler = new Handler();
        statusField = (TextView) findViewById(R.id.statusField);

        Platform.loadPlatformComponent(new AndroidPlatformComponent());
        // Change to the IP address and matching port of your SignalR server.
        String host = "http://192.168.1.5:8080/";
        HubConnection connection = new HubConnection( host );
        HubProxy hub = connection.createHubProxy( "MessageHub" );
        ClientTransport transport = new ServerSentEventsTransport(connection.getLogger());

        SignalRFuture<Void> awaitConnection = connection.start(transport);
        try {
            awaitConnection.get();
        }
        catch (InterruptedException e) {
            Log.d("CHECK", e.toString());
            e.printStackTrace();
        } catch (ExecutionException e) {
            Log.d("CHECK", e.toString());
            e.printStackTrace();
        }

        hub.subscribe(this);

        try {
            hub.invoke( "SendMessage", "Client", "Hello world!" ).get();
            hub.invoke( "SendCustomType",
                    new CustomType() {{ Name = "Universe"; Id = 42; }} ).get();
        } catch (InterruptedException e) {
            // Handle ...
        } catch (ExecutionException e) {
            // Handle ...
        }

    }

    public void UpdateStatus(String status) {
        final String fStatus = status;
        handler.post(new Runnable() {
            @Override
            public void run() {
                statusField.setText(fStatus);
            }
        });
    }

    public class CustomType
    {
        public String Name;
        public int Id;
    }

但是，我最终遇到了一个挂起的屏幕，它什么都不显示，而且应用程序停止响应。 android 记录器显示以下错误:

java.util.concurrent.ExecutionException: java.net.ConnectException: failed to connect to localhost/127.0.0.1 (port 80) after 15000ms: isConnected failed: ECONNREFUSED (Connection refused)

我的代码是否正确，我是否正确遵循了指南？这是一个非常直接的指南，但出现了这个问题。有人可以帮忙吗？

编辑:

This 是一个非常相似的问题，实际上它描述的是同一个问题。然而，这对我没有任何好处。如果您注意到我的 android 代码，我已经在那个问题中提出了这些更改。仍然没有解决问题。

堆栈跟踪

 java.util.concurrent.ExecutionException: java.net.SocketTimeoutException: failed to connect to / 192.168.1.5(port 8080) after 15000ms
 at microsoft.aspnet.signalr.client.SignalRFuture.get(SignalRFuture.java: 112)
 at microsoft.aspnet.signalr.client.SignalRFuture.get(SignalRFuture.java: 102)
 at com.example.dinuka.signalrtest.Main2Activity.onCreate(Main2Activity.java: 40)
 at android.app.Activity.performCreate(Activity.java: 6289)
 at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java: 1119)
 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java: 2655)
 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java: 2767)
 at android.app.ActivityThread.access$900(ActivityThread.java: 177)
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java: 1449)
 at android.os.Handler.dispatchMessage(Handler.java: 102)
 at android.os.Looper.loop(Looper.java: 145)
 at android.app.ActivityThread.main(ActivityThread.java: 5951)
 at java.lang.reflect.Method.invoke(Native Method)
 at java.lang.reflect.Method.invoke(Method.java: 372)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java: 1400)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java: 1195)
 Caused by: java.net.SocketTimeoutException: failed to connect to / 192.168.1.5(port 8080) after 15000ms
 at libcore.io.IoBridge.connectErrno(IoBridge.java: 169)
 at libcore.io.IoBridge.connect(IoBridge.java: 122)
 at java.net.PlainSocketImpl.connect(PlainSocketImpl.java: 183)
 at java.net.PlainSocketImpl.connect(PlainSocketImpl.java: 456)
 at java.net.Socket.connect(Socket.java: 882)
 at com.android.okhttp.internal.Platform.connectSocket(Platform.java: 139)
 at com.android.okhttp.Connection.connect(Connection.java: 1194)
 at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java: 392)
 at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java: 295)
 at com.android.okhttp.internal.http.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java: 373)
 at com.android.okhttp.internal.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java: 323)
 at com.android.okhttp.internal.http.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java: 491)
 at microsoft.aspnet.signalr.client.http.java.NetworkRunnable.run(NetworkRunnable.java: 72)
 at java.lang.Thread.run(Thread.java: 818)

Answer 1

几天前我遇到了类似的问题，这个 Github 问题对我有所帮助: https://github.com/SignalR/java-client/issues/63

基本上我所做的就是修改 signalr-client-sdk 项目中的 WebsocketTransport.java。替换:

uri = new URI(url);

与

uri = new URI(url.replace("http://", "ws://"));

源代码中的第 86 行左右。

我现在可以连接并发送消息并接收原始数据，但无法订阅事件...

希望这可以帮助您解决问题。