Question

我已经阅读了这些主题：
how to use SignalR in Android
Android Client doesn't get data but .net client getting data from SignalR server

我用Android编写了一个与SignalR配合使用的简单聊天系统它应该是客户端发送消息（通过在服务器上调用SendMessage方法），服务器应该在客户端上调用NewMessage方法。

这是我用C＃编写的ChatHub类（简化）。

public class ChatHub : Hub
{
    // Store the clients connections Id
    static readonly List<string> _connectedClients;

    public override Task OnConnected()
    {
        // Keep connections id
        // This section works fine and when the android device connects to the server,
        // Its connection id will stored.
        _connectedClients.Add(Context.ConnectionId)

        //... other codes
    }

    public void SendMessage(string message)
    {
        foreach (var connectionId in _connectedClients)
        {
            // according to the logs 
            // android device connection id exists here
            // and it works fine.
            Clients.Client(connectionId).NewMessage(message);
        }
    }
}

当android客户端连接到服务器时，在OnConnected方法上，连接ID将存储在_connectedClients中，并且工作正常。

在SendMessage类的ChatHub方法中，我们有android设备连接ID，我确定Android设备在列表中

这是我的Andoird代码：

public class ChatActivity extends AppCompatActivity
{
    // private fields
    HubConnection connection;
    HubProxy hub;
    ClientTransport transport;

    protected void onCreate(Bundle savedInstanceState) {

        Logger logger = new Logger() {
            @Override
            public void log(String message, LogLevel logLevel) {
                Log.e("SignalR", message);
            }
        };

        Platform.loadPlatformComponent(new AndroidPlatformComponent());
        connection = new HubConnection("192.168.1.100");
        hub = connection.createHubProxy("chatHub"); // case insensitivity

        transport = new LongPollingTransport(connection.getLogger());

        // no difference when using this:
        //transport = new ServerSentEventsTransport(connection.getLogger());

        // this event never fired!
        hub.subscribe(new Object() {
            public void NewMessage(String message)
            {
                Log.d("<Debug", "new message received in subscribe"); // won't work!
            }
        }

        // this event never fired!
        hub.on("NewMessage", new SubscriptionHandler() {
            @Override
            public void run() {
                Log.d("<Debug", "new message received in `on`"); // won't work!
            }
        });

        // connect to the server that works fine.
        SignalRFuture<Void> awaitConnection = connection.start(transport);
        try {
            awaitConnection.get(); // seems useless when using this or not!
        }
        catch (Exception ex) {
        }

        // this method works fine.
        hub.invoke("sendMessage", "this is a test message to the server")
        .done(new Action<Void>() {
                @Override
                public void run(Void aVoid) throws Exception {
                    Log.d("<Debug", "message sent."); // Works fine
                }
        });

    }
}

在上面的 java 代码中，调用服务器上的sendMessage工作正常，服务器获取消息。
但唯一的问题是服务器永远不会调用hub.on(...)或hub.subscribe(...)事件在一个简单的描述中，我的应用程序可以发送消息，但无法接收来自其他人的消息任何建议将不胜感激。

Answer 1

您不在客户端提供与参与方相同的参数。代码应该如下：

      hub.on("NewMessage", new SubscriptionHandler1<String>() {
        @Override
        public void run(String message) {
            Log.d("<Debug", "new message received in `on`"); 
        }
    },String.class);  //do not forget say the String class in the end

Android应用未收到来自SignalR hub

1 个答案: