I am trying to build a website that displays a google map with a user location (lat/long) from a php service that I wrote.
I already have a php script that gets the lat/long from a mobile app (via POST from the client), stores it in a DB, and read it back from the DB into two variables, let's call them $lat and $long. To make sure I have the right values in $lat and $long, I did a simple echo and got the two values.
I am struggling with understanding how to read these values from my index.html script. All the examples that I have seen suggest keeping the php code in the html file but I would rather keep them separate. I am also not sure how to assign these values to parameters in HTML/Javacript so I can actually display them on the map.
So my questions are: 1. how do I call that php file from HTML? 2. and how do I read $lat and $long from the php service and assign them to parameters in HTML/Javascript that I can display on the map?
EDIT: here is my PHP code and my index.html (Which is a 1:1 copy from the Google Maps v3 docs).
location.php:
$content = file_get_contents('php://input');
$post_data = json_decode($content , true);
$lat = $post_data['lat'];
$long = $post_data['long'];
//CONNECT TO MYSQL
$con1 = mysql_connect("localhost", "xxxxx", "yyyy", "zzzzz");
if ($con1->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
}
if (!$db_selected) {
die ('Can\'t use foo : ' . mysql_error());
}
if (!empty($lat)) {
$sql = "INSERT INTO LocationInfo (latitude, longitude)
VALUES ('$lat', '$long');";
mysql_query($sql) or die ('Error updating database: ' . mysql_error());
}
$read_query = "SELECT * FROM LocationInfo;";
$results = mysql_query($read_query) or die ('Error reading from database: ' . mysql_error());
$column = array();
while($row = mysql_fetch_array($results)){
$column[] = $row;
}
$current_lat = $column[sizeof($column) - 1]['latitude'];
$current_long = $column[sizeof($column) - 1]['longitude'];
echo $current_lat;
echo $current_long;
?>
index.html:
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>My GeoLocation</title>
<style>
html, body, #map-canvas {
height: 100%;
margin: 0px;
padding: 0px
}
</style>
<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&signed_in=true"></script>
<script>
var map;
function initialize() {
var mapOptions = {
zoom: 14
};
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
if(navigator.geolocation) {
navigator.geolocation.getCurrentPosition(function(position) {
var pos = new google.maps.LatLng(position.coords.latitude,
position.coords.longitude);
var infowindow = new google.maps.InfoWindow({
map: map,
position: pos,
content: 'Location found using HTML5.'
});
The easiest way to get those variables in Javascript is to output them from PHP to JS, there is no direct bridge, so you will need in the HTML output a script block with the values you got from your SQL query, it will be something like this:
<script>
var lat = <?php echo $lat ?>;
var long = <?php echo $long ?>;
</script>
Now you can use this variables in your javascripts to invoke the map, as a note you can add the variables definition to your main JS block as well.
EDIT: Rename index.html to index.php
<?php include_once('location.php') ?>
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>My GeoLocation</title>
<style>
html, body, #map-canvas {
height: 100%;
margin: 0px;
padding: 0px
}
</style>
<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&signed_in=true"></script>
<script>
var map;
function initialize() {
// var myLatlng = new google.maps.LatLng(<?php echo $lat ?>,<?php echo $long ?>);
var mapOptions = {
zoom: 14
//mapTypeId: google.maps.MapTypeId.ROADMAP
//center: myLatlng
};
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
if(navigator.geolocation) {
navigator.geolocation.getCurrentPosition(function(position) {
var pos = new google.maps.LatLng(position.coords.latitude,
position.coords.longitude);
var infowindow = new google.maps.InfoWindow({
map: map,
position: pos,
content: 'Location found using HTML5.'
});