截击服务器停机错误

Question

我想知道当我发出请求时服务器是否关闭，基本上我正在尝试做一个简单的注册（它已经工作）但是如果当我单击注册时将 nodeJS 服务器关闭它不会在我的吐司上出现任何错误，我试图按照我找到的一些答案进行操作，但没有任何效果

这是我尝试过的：

 public void notifyError(String requestType,VolleyError error) {
                String body;
                if(error.networkResponse.data!=null) {
                    String statusCode = String.valueOf(error.networkResponse.statusCode);
                    try {
                        if (error instanceof NetworkError) {
                            Log.d("internet","nao tem internet ligada");
                        }
                        else if (error instanceof ServerError) {
                            Log.d("internet","The server could not be found. Please try again after some time!!");
                        }
                        body = new String(error.networkResponse.data,"UTF-8");
                        JSONObject jsonObj = new JSONObject(body);
                        Log.d("body",String.valueOf(jsonObj.get("message")));
                        showToast(String.valueOf(jsonObj.get("message")));
                    } catch (UnsupportedEncodingException e) {
                        showToast("You need to connect to the internet!");
                    } catch (JSONException e) {
                        Log.d("json:","problems decoding jsonObj");
                    }
                }

关于我如何构建凌空示例的任何问题，我都遵循了这个thread

NEtwork error 和 serverError 中的消息从不显示，有什么提示吗？

Answer 1

去掉“if”条件，error.networkResponse.data 返回null。

public void notifyError(String requestType,VolleyError error) {
    String body;
    String statusCode = String.valueOf(error.networkResponse.statusCode);
    try {
        if (error instanceof NetworkError) {
            Log.d("internet","nao tem internet ligada");
        } else if (error instanceof ServerError) {
            Log.d("internet","The server could not be found. Please try again after some time!!");
        }

        body = new String(String.valueOf(error.networkResponse.statusCode),"UTF-8"); 
        JSONObject jsonObj = new JSONObject(body);
        Log.d("body",String.valueOf(jsonObj.get("message")));
        showToast(String.valueOf(jsonObj.get("message")));
    } catch (UnsupportedEncodingException e) {
        showToast("You need to connect to the internet!");
    } catch (JSONException e) {
        Log.d("json:","problems decoding jsonObj");
    }
}