Google Maps API v3: How to Set Zoom Level And Map Center To User Submitted Location?

php javascript mysql google-maps google-maps-api-3
18,286

Solution 1

Since you said this would be used as a Facebook app, I have a friendly suggestion.

Now that your code is working, you should look into wrapping it in its own namespace and implement the module pattern. Doing so will guarantee that your function names, especially load(), do not clash or get overwritten by other apps on the same FB page.

I have created a small sample app here. Yours could be as simple as something like:

if (!window.Carlin) { window.Carling = {}; }
Carlin.Locator = function() {

    var map,markers,infoWindow,locationSelect;

    markers = [];

    function load() {
    }

    function searchLocations() {
    }

    function clearLocations() {
    }

    //...etc

    return {
        init: load
    }
}();

$(document).ready(Carlin.Locator.init);

Solution 2

Found the methods I was looking for in the documentation (surprise, surprise!)

Simply add these two lines under map.fitBounds(bounds); in the searchLocationsNear function:

   map.setZoom(11);
   map.setCenter(center);
Share:
18,286
martincarlin87
Author by

martincarlin87

🏴󠁧󠁢󠁳󠁣󠁴󠁿 Just trying to improve and help if I can. Personal site is martincarlin.uk #SOreadytohelp

Updated on June 13, 2022

Comments

  • martincarlin87
    martincarlin87 almost 2 years

    I have used this tutorial from Google to build a web app that finds the closest store from the user entered location:

    http://code.google.com/apis/maps/articles/phpsqlsearch_v3.html

    I have my app almost working the way I want it, upon page load, the map is loaded, centered and set to zoom level 6 and the user fills out the form with their location.

    The app then pulls all the store info from the db and populates the map with a marker for each.

    The zoom level seems to decrease aswell but I can't find this in the code anywhere.

    What I actually want to do on submit is zoom in to zoom level 6 and center the map to the latitude and longitude of the user entered location and output info on the nearest stores, e.g the nearest 5. I was wondering if anyone here knew how to implement this feature?

    index.php

    <div>
    <input type="text" id="addressInput" size="50"/>
    <input type="hidden" id="radiusSelect" value="5"/>
    <input type="button" onclick="searchLocations()" value="Search"/>
</div>
<div><select id="locationSelect" style="width:100%;visibility:hidden"></select></div>
<div id="map" style="width:100%; height:50%"></div>



<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script src="http://maps.google.com/maps/api/js?sensor=false" type="text/javascript"></script>
<script type="text/javascript">
//<![CDATA[
var map;
var markers = [];
var infoWindow;
var locationSelect;

function load() {
  map = new google.maps.Map(document.getElementById("map"), {
    center: new google.maps.LatLng(54.600939134593, -2.399894114594),
    zoom: 6,
    mapTypeId: 'roadmap',
    mapTypeControlOptions: {style: google.maps.MapTypeControlStyle.DROPDOWN_MENU}
  });
  infoWindow = new google.maps.InfoWindow();

  locationSelect = document.getElementById("locationSelect");
  locationSelect.onchange = function() {
    var markerNum = locationSelect.options[locationSelect.selectedIndex].value;
    if (markerNum != "none"){
      google.maps.event.trigger(markers[markerNum], 'click');
    }
  };
}

function searchLocations() {
 var address = document.getElementById("addressInput").value;
 var geocoder = new google.maps.Geocoder();
 geocoder.geocode({address: address}, function(results, status) {
   if (status == google.maps.GeocoderStatus.OK) {
    searchLocationsNear(results[0].geometry.location);
   } else {
     alert(address + ' not found');
   }
 });
}

function clearLocations() {
 infoWindow.close();
 for (var i = 0; i < markers.length; i++) {
   markers[i].setMap(null);
 }
 markers.length = 0;

 locationSelect.innerHTML = "";
 var option = document.createElement("option");
 option.value = "none";
 option.innerHTML = "See all results:";
 locationSelect.appendChild(option);
}

function searchLocationsNear(center) {
 clearLocations(); 

 var radius = document.getElementById('radiusSelect').value;
 var searchUrl = 'phpsqlsearch_genxml.php?lat=' + center.lat() + '&lng=' + center.lng() + '&radius=' + radius;
 downloadUrl(searchUrl, function(data) {
   var xml = parseXml(data);
   var markerNodes = xml.documentElement.getElementsByTagName("marker");
   var bounds = new google.maps.LatLngBounds();
   for (var i = 0; i < markerNodes.length; i++) {
     var town = markerNodes[i].getAttribute("town");
     var postcode = markerNodes[i].getAttribute("postcode");
     var name = markerNodes[i].getAttribute("name");
     var address = markerNodes[i].getAttribute("address");
     var distance = parseFloat(markerNodes[i].getAttribute("distance"));
     var latlng = new google.maps.LatLng(
          parseFloat(markerNodes[i].getAttribute("lat")),
          parseFloat(markerNodes[i].getAttribute("lng")));

    var id = markerNodes[i].getAttribute("id");
    var fname = markerNodes[i].getAttribute("fname");
    var link = '<a href="http://www.domain.co.uk/stores/' + fname + '-' + id + '.html" target="_blank" title="Store: ' + town + '">More info</a>';

     createOption(name, distance, i);
     createMarker(latlng, name, address, town, postcode, link);
     bounds.extend(latlng);
   }
   map.fitBounds(bounds);
   locationSelect.style.visibility = "visible";
   locationSelect.onchange = function() {
     var markerNum = locationSelect.options[locationSelect.selectedIndex].value;
     google.maps.event.trigger(markers[markerNum], 'click');
   };
  });
 }

 function createMarker(latlng, name, address, town, postcode, link) {
  var html = "<b>" + town + "</b> <br/>" + address + "<br/>" + postcode + "<br/>" + link;
  var marker = new google.maps.Marker({
    map: map,
    position: latlng
  });
  google.maps.event.addListener(marker, 'click', function() {
    infoWindow.setContent(html);
    infoWindow.open(map, marker);
  });
  markers.push(marker);
}

 function createOption(name, distance, num) {
  var option = document.createElement("option");
  option.value = num;
  option.innerHTML = name + "(" + distance.toFixed(1) + ")";
  locationSelect.appendChild(option);
 }

 function downloadUrl(url, callback) {
  var request = window.ActiveXObject ?
      new ActiveXObject('Microsoft.XMLHTTP') :
      new XMLHttpRequest;

  request.onreadystatechange = function() {
    if (request.readyState == 4) {
      request.onreadystatechange = doNothing;
      callback(request.responseText, request.status);
    }
  };

  request.open('GET', url, true);
  request.send(null);
 }

 function parseXml(str) {
  if (window.ActiveXObject) {
    var doc = new ActiveXObject('Microsoft.XMLDOM');
    doc.loadXML(str);
    return doc;
  } else if (window.DOMParser) {
    return (new DOMParser).parseFromString(str, 'text/xml');
  }
 }

 function doNothing() {}

//]]>
</script>


<script type="text/javascript">
    $(document).ready(function() {
        load();
    });
</script>

    phpsqlsearch_genxml.php

    <?php
$db_conn = mysql_connect('xxx.xxx.xx.xx', 'xxxxxxxx', 'xxxxxx') or die('error');
mysql_select_db('uk_db', $db_conn) or die(mysql_error());

// Get parameters from URL
$center_lat = $_GET["lat"];
$center_lng = $_GET["lng"];
$radius = $_GET["radius"];

if(!$_GET['zoom']) { 
    $_GET['zoom'] = 11; 
}

// Start XML file, create parent node
$dom = new DOMDocument("1.0");
$node = $dom->createElement("markers");
$parnode = $dom->appendChild($node);


// Select all the rows in the markers table
$query = 'SELECT address1, address2, address3, longitude, latitude, name, town, store_id, postcode, storenumber 
          FROM uk_store
          WHERE isActive=1 ';
if($_GET["region"] != '') {
    $query .= ' AND region = "' . $_GET["region"] . '"';
} else {
    $query .= ' AND region in("Scotland", "England", "Wales", "Northern Ireland") ';
}

// lets start to check what has been search on
if($_GET['postcode'] != '') {

  //lets make sure postcode only has numbers letter and spaces
  $searchparams .= 'postcode=' . $_GET['postcode'] . '&amp;';
  $postcode = $_GET['postcode'];
  $postcode = verifyInput($postcode);
  $query .= " AND postcode = '" . $postcode . "'";

}

if($_GET['town'] != '') {
    // make sure town only has letters or spaces.
    $searchparams .= 'town=' . $_GET['town'] . '&amp;';
    $town = $_GET['town']; 
    $town = verifyInput($town);
    $query .= " AND town = '" . $town . "'";
}

if($_GET['min_lat'] && $_GET['min_long'] && $_GET['max_lat'] && $_GET['max_long'] ) {
   $query .=   " AND latitude BETWEEN " . $_GET['min_lat'] . " AND " . $_GET['max_lat'] . " AND longitude BETWEEN " . $_GET['min_long'] . " AND " . $_GET['max_long'] ;
   $mapsearch = 1;
}

if(!($_GET['postcodeLat'] && $_GET['postcodeLong'])) {
    $query .= " ORDER BY Region, Town , Name "; 
}

$result = mysql_query($query);
if (!$result) {
  die("Invalid query: " . mysql_error());
}

header("Content-type: text/xml");

echo '<markers>';

if($_GET['postcodeLat'] && $_GET['postcodeLong'])
{
    $count = 0;

   // we need to sort the results by distance
    while ($row = @mysql_fetch_array($result, MYSQL_ASSOC))
    {
        $address = $row['address1'] . ' ' . $row['address2'] . ' ' . $row['address3'];
        $distance = distance($_GET['postcodeLat'], $_GET['postcodeLong'], $row['latitude'], $row['longitude']); 
        $row['distance'] = number_format($distance, 2);
        $row['fname'] = $row['town'] . '-' . $row['name'];
        $row['fname'] = str_replace("'",'', $row['fname']);
        $row['fname'] = ereg_replace(' ','-', $row['fname']); 
        $row['fname'] = ereg_replace('\/','-', $row['fname']);
        $row['fname'] = ereg_replace('\(','', $row['fname']);
        $row['fname'] = ereg_replace('\)','', $row['fname']);
        $row['fname'] = strtolower($row['fname']);
        //get distance and add to $row array
        $results[$distance.$row['id']] = $row;        
    } 

    ksort($results);

    foreach ($results as $key => $row) 
    {
      // ADD TO XML DOCUMENT NODE 
        $address = $row['address1'] . ' ' . $row['address2'] . ' ' . $row['address3'];  
        echo '<marker ';  
        echo 'name="' . parseToXML($row['name']) . '" ';  
        echo 'fname="' . parseToXML($row['fname']) . '" '; 
        echo 'town="' . parseToXML($row['town']) . '" ';  
        echo 'lat="' . $row['latitude'] . '" ';  
        echo 'lng="' . $row['longitude'] . '" ';  
        echo 'id="' . $row['store_id'] . '" ';  
        echo 'address="' . $address . '" '; 
        echo 'distance="' . $row['distance'] . '" '; 
        echo 'postcode="' . $row['postcode'] . '" ';
        echo 'storenumber="' . $row['storenumber'] . '" ';
        echo 'address1="' . parsetoXml($row['address1']). '" '; 
        echo 'address2="' . parsetoXml($row['address2']). '" '; 
        echo 'address3="' . parsetoXml($row['address3']). '" ';
        echo '/>';
    }

}
else
{
    // Iterate through the rows, printing XML nodes for each
    while ($row = @mysql_fetch_assoc($result))
    {
         $address = $row['address1'] . ' ' . $row['address2'] . ' ' . $row['address3'];
         $row['fname'] = $row['town'] . '-' . $row['name'];
         $row['fname'] = ereg_replace(' ','-', $row['fname']); 
         $row['fname'] = ereg_replace('\/','-', $row['fname']);
         $row['fname'] = ereg_replace('\(','', $row['fname']);
         $row['fname'] = ereg_replace('\)','', $row['fname']);

        // ADD TO XML DOCUMENT NODE  
        echo '<marker ';  
        echo 'name="' . parseToXML($row['name']) . '" ';
        echo 'fname="' . strtolower(parseToXML($row['fname'])) . '" '; 
        echo 'town="' . parseToXML($row['town']) . '" ';  
        echo 'lat="' . $row['latitude'] . '" ';  
        echo 'lng="' . $row['longitude'] . '" ';  
        echo 'id="' . $row['store_id'] . '" ';  
        echo 'isSurg="' . $row['isLaserSurgery'] . '" '; 
        echo 'isCons="' . $row['isLaserConsult'] . '" '; 
        echo 'address="' . parsetoXml($address). '" '; 
        echo 'address1="' . parsetoXml($row['address1']). '" '; 
        echo 'address2="' . parsetoXml($row['address2']). '" '; 
        echo 'address3="' . parsetoXml($row['address3']). '" '; 
        echo 'postcode="' . $row['postcode'] . '" '; 
        echo 'storenumber="' . $row['storenumber'] . '" ';
        echo '/>';
    }
}
// End XML file
echo '</markers>';


// make sure the data is xml friendly
function parseToXML($htmlStr) 
{ 
    $xmlStr=str_replace('<','&lt;',$htmlStr); 
    $xmlStr=str_replace('>','&gt;',$xmlStr); 
    $xmlStr=str_replace('"','&quot;',$xmlStr); 
    //$xmlStr=str_replace("'",'&#39;',$xmlStr); 
    $xmlStr=str_replace("&",'&amp;',$xmlStr); 
    return $xmlStr; 
}

// calculate the distance in miles or kms between any two points 
function distance($lat1, $lon1, $lat2, $lon2, $unit = '') { 
    $theta = $lon1 - $lon2; 
    $dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) +  cos(deg2rad($lat1)) * cos(deg2rad($lat2)) * cos(deg2rad($theta)); 
    $dist = acos($dist); 
    $dist = rad2deg($dist); 
    $miles = $dist * 60 * 1.1515;
    if($unit != '')
    {
        $unit = strtoupper($unit);
    }

if ($unit == "K") {
    return ($miles * 1.609344); 
} else if ($unit == "N") {
  return ($miles * 0.8684);
} else {
    return $miles;
  }
} 

function VerifyInput ($input, $forceInt = false) { 

if (is_numeric($input)) { 
    return $input; 
} elseif (!$forceInt) { 

    if (get_magic_quotes_gpc() && trim(ini_get("magic_quotes_sybase")) == "") { 
        $input = stripslashes($input); 
        $input = str_replace("'", "", $input); 
        $input = str_replace("`", "", $input);
    } elseif (!get_magic_quotes_gpc()) { 
        $input = str_replace("'", "", $input);
        $input = str_replace("`", "", $input); 
    } 
    return $input; 
} elseif ($forceInt) { 
    return 0; 
} 
} 

?>

    Apologies, that's a lot of pasting there but I thought it better to include everything rather than risk someone not being able to answer because there wasn't enough detail.

    UPDATE

    I have tried inserting this piece of code into the searchLocations function but it doesn't seem tochange the behaviour in anyway:

    function searchLocations() {
 var address = document.getElementById("addressInput").value;
 var geocoder = new google.maps.Geocoder();
 geocoder.geocode({address: address}, function(results, status) {
   if (status == google.maps.GeocoderStatus.OK) {
    searchLocationsNear(results[0].geometry.location);
    /////////////// new code
    var myOptions = {
    zoom: 11,
    center: address.geometry.location,
    mapTypeId: google.maps.MapTypeId.TERRAIN
    }
    map = new google.maps.Map(document.getElementById("map"), myOptions);
    ////////////////

   } else {
     alert(address + ' not found');
   }
 });
}

Recents

Why Is PNG file with Drop Shadow in Flutter Web App Grainy?
How to troubleshoot crashes detected by Google Play Store for Flutter app
Cupertino DateTime picker interfering with scroll behaviour
Why does awk -F work for most letters, but not for the letter "t"?
Flutter change focus color and icon color but not works
How to print and connect to printer using flutter desktop via usb?
Critical issues have been reported with the following SDK versions: com.google.android.gms:play-services-safetynet:17.0.0
Flutter Dart - get localized country name from country code
navigatorState is null when using pushNamed Navigation onGenerateRoutes of GetMaterialPage
Android Sdk manager not found- Flutter doctor error
Flutter Laravel Push Notification without using any third party like(firebase,onesignal..etc)
How to change the color of ElevatedButton when entering text in TextField

Related

Displaying google map with markers using data from mysql (laravel)
Uncaught InvalidValueError: not an Array
Create Google Map Markers with PHP
Drawing Multiple Polygons on Google Maps API v3 from MySQL database
PHP: calling javascript function with parameters from php
Real time tracking in google map
How to add marker on map by Click using react-google-maps?
Google maps API - Uncaught ReferenceError: directionsService is not defined
Radius Search PHP, MYSQL and Google Maps
Google Maps SetCenter. Focus on new location