Android Volley - BasicNetwork.performRequest: Unexpected response code 400

Question

Problem: When I click register button, its show blank toast only and didnt insert data on my online database webserver.

Old Code on onErrorResponse:

public void onErrorResponse(VolleyError error) {
         progressDialog.hide();
                 Toast.makeText(getApplicationContext(),error.getMessage(), Toast.LENGTH_LONG).show();

}

Searched solution:

Android Volley - BasicNetwork.performRequest: Unexpected response code 400

New Problem: I am stuck in "registering user ..." when I add data and clicked register button.

Logcat errors:

E/Volley: [166] BasicNetwork.performRequest: Unexpected response code 400 for *htt://HOSTURL.com* registerUser.php

and

E/Surface: getSlotFromBufferLocked: unknown buffer: 0xa2565120

Source Code:

package com.chishingwan.loginregister;

import android.app.ProgressDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.android.volley.AuthFailureError;
import com.android.volley.NetworkResponse;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.ServerError;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.HttpHeaderParser;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import org.json.JSONException;
import org.json.JSONObject;

import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;

public class RegisterActivity extends AppCompatActivity implements View.OnClickListener {

    private EditText etFirstName, etLastName, etAddress, etContactNumber, etEmail, etPassword;
    private Button bRegister;
    private ProgressDialog progressDialog;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);

        etFirstName = (EditText) findViewById(R.id.etFirstName);
        etLastName = (EditText) findViewById(R.id.etLastName);
        etAddress = (EditText) findViewById(R.id.etAddress);
        etContactNumber = (EditText) findViewById(R.id.etContactNumber);
        etEmail = (EditText) findViewById(R.id.etEmail);
        etPassword = (EditText) findViewById(R.id.etPassword);
        bRegister = (Button) findViewById(R.id.bRegister);
        progressDialog = new ProgressDialog(this);

        bRegister.setOnClickListener(this);

    }

    private void registerUser(){
        final String firstname = etFirstName.getText().toString().trim();
        final String lastname = etLastName.getText().toString().trim();
        final String contactnumber = etContactNumber.getText().toString().trim();
        final String address = etAddress.getText().toString().trim();
        final String email = etEmail.getText().toString().trim();
        final String password = etPassword.getText().toString().trim();

        progressDialog.setMessage("Registering user ... ");
        progressDialog.show();

        StringRequest stringRequest = new StringRequest(Request.Method.POST, Constants.URL_REGISTER,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        progressDialog.dismiss();

                        try{
                            JSONObject jsonObject = new JSONObject(response);
                            Toast.makeText(getApplicationContext(), jsonObject.getString("message"), Toast.LENGTH_LONG).show();
                        }catch(JSONException e){
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        NetworkResponse response = error.networkResponse;
                        if (error instanceof ServerError && response != null) {
                            try {
                                String res = new String(response.data,
                                        HttpHeaderParser.parseCharset(response.headers, "utf-8"));
                                // Now you can use any deserializer to make sense of data
                                JSONObject obj = new JSONObject(res);
                            } catch (UnsupportedEncodingException e1) {
                                // Couldn't properly decode data to string
                                e1.printStackTrace();
                            } catch (JSONException e2) {
                                // returned data is not JSONObject?
                                e2.printStackTrace();
                            }
                        }
                    }
                }){
            @Override
            protected Map<String, String> getPostParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<>();
                params.put("firstname", firstname);
                params.put("lastname", lastname);
                params.put("address", address);
                params.put("contactnumber", contactnumber);
                params.put("email", email);
                params.put("password", password);

                return params;
            }
        };
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        requestQueue.add(stringRequest);
    }

    @Override
    public void onClick(View view) {

        if(view==bRegister){
            registerUser();
        }
    }
}

Answer 1

You forgot to add header to your StringRequest:

@Override
public Map<String, String> getHeaders() throws AuthFailureError {
    Map<String, String> header = new LinkedHashMap<String, String>();
    header.put("Content-Type", "application/x-www-form-urlencoded");
    return super.getHeaders();
}