Check out Lines Galaxy Android game to view the results in action.

Most common ways to communicate between your mobile app to your backend servers are HTTP Requests and Websockets.

In this article I’ll describe how you can create, send and process a HTTP Request to backend servers from your LibGDX application. In this example I will demonstrate how to send a basic POST request.

First step is to prepare the request payload:

Map<String, String> parameters = new HashMap<String, String>();

parameters.put("token", "<TOKEN>");
parameters.put("some_value", 1234);

final Json json = new Json();
json.setTypeName(null);
json.setOutputType(JsonWriter.OutputType.json);
json.setUsePrototypes(false);
String requestJson = json.toJson(parameters);

Second step is to create an instance of the HTTP Agent:

Net.HttpRequest request = new Net.HttpRequest(Net.HttpMethods.POST);
request.setUrl("http://example.com/");
request.setContent(requestJson);

And finally, after we set the desired server url and prepared the payload, we can send the request and attach the callback listeners

Gdx.net.sendHttpRequest(request, new Net.HttpResponseListener() {
    public void handleHttpResponse(Net.HttpResponse httpResponse) {
        HttpStatus status = httpResponse.getStatus();
        if(status.getStatusCode() == 200) {
            String responseJson = httpResponse.getResultAsString();
        } else {
            // error :(
        }
    }
    public void failed(Throwable t) {
        String error = t.getMessage();
    }
    public void cancelled() {
        // request aborded
    }
});

And that’s it. ou can just copy the above code and send LibGDX HTTP Request. You can dig further by reading the official docs: HttpResponseListener, HttpRequest.

Check out Lines Galaxy Android game to view the results in action.