Question

只要fb_flag为1，就在Listener中获取错误，m只是初学者;学习排球

NullPointerException ::: 试图解决错误;但是无法解决它

LoginCall.java

public class Login_Call {
    Context con;
    String email ="", pass = "";
    String fb_flag = String.valueOf(0);
    String URL = "";
    UserData userData;
    String Message = "Success";

用于设置数据项的构造函数;

    public Login_Call(Context context, String email, String password, String flag) {
        con = context;
        this.email = email;`enter code here`
        pass = password;
        fb_flag = flag;
        Toast.makeText(con,fb_flag, Toast.LENGTH_SHORT).show();
    }

    public UserData getUserDataObject() {
        return userData;
    }

在此方法中出错; 方法用于使用url;

映射字符串数据

    public String getLoginAcc() {
        RequestQueue queue = Volley.newRequestQueue(con);
        StringRequest postRequest = new StringRequest(Method.POST, URL, new Listener<String>() {
            @Override
            public void onResponse(String s) {
                Log.d("LoginCheck", s);
                Toast.makeText(con,s, Toast.LENGTH_SHORT).show();
                authenticateLoginResponse(s);
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError volleyError) {
                Toast.makeText(con, "Server Not Responding" + volleyError, Toast.LENGTH_SHORT).show();
            }
        }) {
            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<String, String>();
                params.put("fb_flag", fb_flag);
                params.put("email", email);
                params.put("password", pass);
                return params;

            }
        };
        postRequest.setTag("Publiko Login");
        postRequest.setRetryPolicy(new DefaultRetryPolicy(5000, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));
        queue.add(postRequest);
        return Message;
    }

    private void authenticateLoginResponse(String data) {
        String response;
        try {
            JSONObject responseObject = new JSONObject(data);
            response = responseObject.getString("response");
            if (response.equals("success")) {
                // ToDo succes response Login Acces Granted
                JSONArray responseArray = responseObject.getJSONArray("data");
                JSONObject reponseInnerObject = responseArray.getJSONObject(0);
                UserData user = new UserData();
                user.setUsername(reponseInnerObject.getString("user_name"));
                user.setEmail(reponseInnerObject.getString("email"));
                user.setAddress(reponseInnerObject.getString("address"));
                user.setPhone(reponseInnerObject.getString("phone"));
                user.setUserid(reponseInnerObject.getString("user_id"));
                userData = user;
            } else {
                // ToDo Failed Response Invalid Email/Password
                this.Message = responseObject.getString("message");
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }
}

提前感谢：）

Answer 1

仔细检查您的网址，看看它是否是有效的网址。在我的情况下，我错过了基本网址。

com.android.volley.VolleyError：java.lang.NullPointerException：尝试在java.lang.String.length（）＆＃39;中调用虚方法＆＃39;在对象引用上

1 个答案: