Android将纬度经度值发送到MySQL数据库

Question

我正在尝试使用php将我的纬度和经度值发送到我的数据库。我有一个EditText，允许用户将他们的UserID发送到数据库工作正常，但当我尝试发送我的纬度和经度时，它无法将其添加到数据库。对于UserID，它是一个editText但我的lat和long是一个setText / textView。

将lat和long设置为textViews：

if (l != null) {     //get latitude and longitude of the location
        double lng = l.getLongitude();
        double lat = l.getLatitude();
        //display on text view
        ln.setText("" + lng);
        lt.setText("" + lat);
    } else {
        ln.setText("No Provider");
        lt.setText("No Provider");
    }
}

@Override
public void onLocationChanged(Location location) {
    double lng = location.getLongitude();
    double lat = location.getLatitude();
    //display on text view
    ln.setText("" + lng);
    lt.setText("" + lat);

添加到数据库：

private void addEmployee(){

        final String TextUserID = editTextUserID.getText().toString().trim();
    final String lon = ln.getText().toString().trim();
    final String lat = lt.getText().toString().trim();

    class AddEmployee extends AsyncTask<Void,Void,String>{

        ProgressDialog loading;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            loading = ProgressDialog.show(MainActivity.this,"Adding...","Wait...",false,false);
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            loading.dismiss();
            Toast.makeText(MainActivity.this,s,Toast.LENGTH_LONG).show();
        }

        @Override
        protected String doInBackground(Void... v) {
            HashMap<String,String> params = new HashMap<>();
            params.put(Config.KEY_EMP_ID, TextUserID);
            params.put(Config.KEY_LAT,lat);
            params.put(Config.KEY_LON,lon);

Config.KEY_EMP_ID，Config.KEY_LAT，Config.KEY_LAT在我的Config.java中声明：

 public static final String KEY_EMP_ID = "UserID";
 public static final String KEY_LAT = "Latitude";
 public static final String KEY_LON = "Longitude";

addEmp.php

<?php 
if($_SERVER['REQUEST_METHOD']=='POST'){

    //Getting values
    $UserID = $_POST['UserID'];
    $Latitude = $_POST['Latitude'];
    $Longitude = $_POST['Longitude'];

    //Creating an sql query
    $sql = "INSERT INTO locationtrace (UserID,Latitude,Longitude,) VALUES ('$UserID','$Latitude','$Longitude')";

    //Importing our db connection script
    require_once('dbConnect.php');

    //Executing query to database
    if(mysqli_query($con,$sql)){
        echo 'Added Successfully';
    }else{
        echo 'Could Not Add To Database!';
    }

    //Closing the database 
    mysqli_close($con);
}