Android Volley error.getMessage() 为空白

Question

所以我正在向我的服务器发送 POST JSonObjectRequest，当它成功时一切正常并且信息被发布，但是如果有错误并且我尝试在 toast 中显示它，它显示为空白。这是我的要求:

private void logUserIn() {
    final String URL = Globals.BASE_URL +"/auth/login/";
    // Post params to be sent to the server
    HashMap<String, String> params = new HashMap<String, String>();
    params.put("username", username.getText().toString());
    params.put("password", password.getText().toString());

    JsonObjectRequest req = new JsonObjectRequest(URL, new JSONObject(params),
            new Response.Listener<JSONObject>() {
                @Override
                public void onResponse(JSONObject response) {
                    try {
                        Log.d("Log In User", response.toString());

                        //logged in db, changes screens
                        Intent nextScreen = new Intent(getApplicationContext(), MyProfile.class);
                        startActivity(nextScreen);
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            Toast.makeText(getApplicationContext(), error.getMessage(), Toast.LENGTH_SHORT).show();
            VolleyLog.e("Error: ", error.getMessage());
        }
    });

    // add the request object to the queue to be executed
    Globals.mRequestQueue.add(req);
}

error.getMessage() 总是空白。这是我在服务器返回错误时的响应(使用 CURL 测试):

{ “非字段错误”:[ “无法使用提供的凭据登录。” ]

我似乎无法打印此消息。我错过了什么？ POST 有效，但错误响应显示为空白...

Answer 1

VolleyError 对象有一个 networkResponse 引用，尝试检查它看看是否可以从那里获得一些有用的信息。

@Override
public void onErrorResponse(VolleyError error) {
    if (error == null || error.networkResponse == null) {
        return;
    }

    String body;
    //get status code here
    final String statusCode = String.valueOf(error.networkResponse.statusCode);
    //get response body and parse with appropriate encoding
    try {
        body = new String(error.networkResponse.data,"UTF-8");
    } catch (UnsupportedEncodingException e) {
        // exception
    }

    //do stuff with the body...
}