如何在android中检查信号器集线器连接是否在线？

Question

我正在使用 signalr 进行聊天 api，signalr 服务正在启动并在一段时间内获取聊天消息，但一段时间后，signalr hub 连接没有响应并且我无法与 signalR 服务器联系。如何在android中检查signalr hubconnection是否在线。

Answer 1

当你调用这个方法而不是通过这个实例时，你可以获得集线器连接的当前状态。

private void startSignalR() {
        Platform.loadPlatformComponent(new AndroidPlatformComponent());
        mInstance.setmHubConnection(getApplicationContext());
        mInstance.setHubProxy();
        ClientTransport clientTransport = new ServerSentEventsTransport(mInstance.mHubConnection.getLogger());
        signalRFuture = mInstance.mHubConnection.start(clientTransport);
        try {
            signalRFuture.get();
        } catch (InterruptedException | ExecutionException e) {
            SharedPrefUtil.clearAllSharedPreferences(getApplicationContext());
            Toast.makeText(getApplicationContext(), getString(R.string.wrong_server), Toast.LENGTH_LONG).show();
            Log.e("SimpleSignalR", e.toString());
            return;
        }

        mInstance.mHubConnection.error(new ErrorCallback() {

            @Override
            public void onError(Throwable error) {
                error.printStackTrace();
            }
        });

        // Subscribe to the connected event
        mInstance.mHubConnection.connected(new Runnable() {

            @Override
            public void run() {
                System.out.println("CONNECTED");
            }
        });

        mInstance.mHubConnection.reconnected(new Runnable() {

            @Override
            public void run() {

                System.out.println("RECONNECTED");
            }
        });
        // Subscribe to the closed event
        mInstance.mHubConnection.closed(new Runnable() {

            @Override
            public void run() {

                System.out.println("DISCONNECTED");
            }
        });

        mInstance.mHubProxy.on(SignalRConstant.CLIENT_METHOD_BROADAST_MESSAGE,
                new SubscriptionHandler2<String, Object>() {
                    @Override
                    public void run(final String msg, final Object data) {
                        if (msg != null && data != null && !data.equals("")) {
                            Intent intent = new Intent();
                            intent.setAction(MY_ACTION);
                            intent.putExtra("CAPTION", msg);
                            if(msg.equals(SignalRConstant.CAPTION_LOGINPASS))
                            {
                                Gson gson = new GsonBuilder().setDateFormat(AppConstant.DATE_FORMAT).create();
                                intent.putExtra("DATA", gson.toJson(data));
                            }else{
                                intent.putExtra("DATA", data.toString());
                            }
                            sendBroadcast(intent);
                        }
                    }
                }
                , String.class, Object.class);
    }