如何使用volley将数据从android发送到MySQL

Question

我在android中使用库有点新。 我想将简单的登录数据发送到我在php中创建的本地服务器，其目的是将电子邮件和密码存储在db中，然后从中获取数据。 我已经在堆栈溢出中随处可读，但问题还没有解决。

数据未插入数据库中我不知道该问题是什么，您能告诉我代码中的错误是什么吗？

MainActivity
package com.example.furqan.testlocalserver;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.net.Uri;
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.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import java.util.HashMap;
import java.util.Map;
public class MainActivity extends AppCompatActivity {

    EditText mEmail, mPassword;
    Button mSaveButton;
    String server_url = "http://127.0.0.1/update_info.php";
    AlertDialog.Builder builder;

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

        mEmail = (EditText) findViewById(R.id.email);
        mPassword = (EditText) findViewById(R.id.password);
        mSaveButton = (Button) findViewById(R.id.saveButton);
        builder = new AlertDialog.Builder(this);

        mSaveButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view)
            {
               // Uri.Builder builder = Uri.parse(Links.URL_login).buildUpon();
                //builder.appendQueryParameter("email", "me@email.com");
                //builder.appendQueryParameter("pw", "mypwd");

                //String loginUrl=builder.build().toString();

                StringRequest stringRequest = new StringRequest(Request.Method.POST, server_url,
                        new Response.Listener<String>()
                        {
                            @Override
                            public void onResponse(String response)
                            {

                                builder.setTitle("Server Respond");
                                builder.setMessage("Response :"+response);
                                builder.setPositiveButton("OK", new DialogInterface.OnClickListener()
                                {
                                    @Override
                                    public void onClick(DialogInterface dialogInterface, int i) {

                                        mEmail.setText("");
                                        mPassword.setText("");
                                    }
                                });

                                AlertDialog alertDialog = builder.create();
                                alertDialog.show();

                            }

                        },
                            new Response.ErrorListener()
                            {
                              @Override
                              public void onErrorResponse(VolleyError error)
                              {
                                  Toast.makeText(MainActivity.this, "Error...!!",Toast.LENGTH_SHORT).show();
                                  error.printStackTrace();
                              }
                            })
                        {
                                @Override
                                protected Map<String, String> getParams() throws AuthFailureError
                                {
                                    Map<String,String> params = new HashMap<>();

                                    params.put("email",mEmail.getText().toString());
                                    params.put("pass",mPassword.getText().toString());

                                    return params;
                                }
                            };

                MySingleTon.getInstance(MainActivity.this).addToRequestQueue(stringRequest);

            }
        });
    }
}

update_info.php


<?php

$user_email = $_POST['email'];
$user_pass = $_POST['pass'];

$user = "root";
$password = "";
$host = "localhost";
$db_name = "testdb";

$con = mysqli_connect( $host, $user, $password,$db_name);

$sql = "INSERT INTO login(Email,Password)
        VALUES('$user_email','$user_pass')";

if(mysqli_query($con,$sql))
{
    echo "Data insert Successfully...";
}
else{
    echo "Error while entering data";
}

mysqli_close($con);


?>