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Google Maps Geocode - Results relevance

I am using the basic functionality of Google Maps Javascript API
Code sample from google :
https://developers.google.com/maps/documentation/javascript/examples/geocoding-simple
var geocoder;
var map;
function initialize() {
geocoder = new google.maps.Geocoder();
var latlng = new google.maps.LatLng(-34.397, 150.644);
var mapOptions = {
zoom: 8,
center: latlng
}
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
}
function codeAddress() {
var address = document.getElementById('address').value;
geocoder.geocode( { 'address': address}, function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
map.setCenter(results[0].geometry.location);
var marker = new google.maps.Marker({
map: map,
position: results[0].geometry.location
});
} else {
alert('Geocode was not successful for the following reason: ' + status);
}
});
}
google.maps.event.addDomListener(window, 'load', initialize);
So as you can tell, when we type a street name, even if we have several results, the sample above is just showing one. I already changed that to loop throught all results and it works fine.
My questions are:
The geocoder.geocode results are sorted by any criteria?
If the answer is yes, is it possible to get the results sorted by most relevant / near place of the current user location ? (I will pass the current user location).
Thanks a lot

Closest thing that I know off is using region biasing: https://developers.google.com/maps/documentation/geocoding/intro#RegionCodes

You're using the wrong API for this, try using the Google Places API. This sorts by popularity (preferred).
Or you can use some code to loop through the results and find the distance from the original location. Then you can sort by distance (works, but I think popularity is what you want)

Resetting Center of Map in Google Maps through Javascript

I have an MVC application that is using Google Maps throughout the app. To make things simple, I've created a JavaScript file that initializes the map and sets the map display.
In my application, I want to allow a front end developer to change the center of the map location with a simple JavaScript call. Unfortunately, after declaring the map and loading the application, if you try to make a JavaScript call back to the map variable, the map JS variable (and all variables) are null. This drops the instance to the map, and does not let me change the location (I believe).
In the JS Code below, I'm trying to call setLocation from the HTML page to reset the location. This is the fail part of the code. Help is appreciated.
var map;
var geocoder;
var marker;
$(document).ready(function () {
initialize();
$(function () {
$("#address").autocomplete({
//This bit uses the geocoder to fetch address values
source: function (request, response) {
geocoder.geocode({ 'address': request.term }, function (results, status) {
response($.map(results, function (item) {
return {
label: item.formatted_address,
value: item.formatted_address,
latitude: item.geometry.location.lat(),
longitude: item.geometry.location.lng()
}
}));
})
},
select: function (event, ui) {
$("#Place_Latitude").val(ui.item.latitude);
$("#Place_Longitude").val(ui.item.longitude);
var location = new google.maps.LatLng(ui.item.latitude, ui.item.longitude);
marker.setPosition(location);
map.setCenter(location);
}
});
});
});
function setLocation(lat, lon) {
var location = new google.maps.LatLng(lat, lon);
marker.setPosition(location);
map.setCenter(location);
}
function initialize() {
var location = new google.maps.LatLng(-34.397, 150.644);
var mapOptions = {
center: location, zoom: 8, mapTypeId: google.maps.MapTypeId.ROADMAP
};
map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);
marker = new google.maps.Marker({
map: map,
draggable: true
});
marker.setPosition(location);
geocoder = new google.maps.Geocoder();
}

This looks bad:
return {
label: item.formatted_address,
value: item.formatted_address,
latitude: item.geometry.location.lat(),
longitude: item.geometry.location.lng()
}
The geocoder is asynchronous and can't return anything from the callback routine. you need to use the variables inside the callback.

There is an example of what you are trying to do here...
Have a look at theie placeMarker function and how they have initialized the map...
My suggestion would be to start with this example and make sure that works. If so, it should be relatively straight forward to determine what is different in your implementation.

better approach then setTimeout on Google Map V3

in my Asp.net Web Application where i am using the setTimeout to Get rid of
geocoder OVER_QUERY_LIMIT, the shorter time out is 10ms which is too longer for me, I have 800 above addresses coming from SQL SERVER which would be increased because of this setTimeout will take about 5 to 7 mints to take places of all the markers on map and that`s frustrating. I researched and saw this link setTimeout: how to get the shortest delay
but cant figure out what he want to do actually. please someone guide me....
function InitializeMap() {
// Here am calling the webService by PageMethods in which CityNames, Countries Name will take their places
PageMethods.GetCitiesbyUser_Extender(onSucess);
var myOptions =
{
zoom: 0,
center: new google.maps.LatLng(-34.397, 150.644),
mapTypeId: google.maps.MapTypeId.ROADMAP,
};
var map = new google.maps.Map(document.getElementById("map"), myOptions);
// Creating latlngbound to bound the markers on map
var bounds = new google.maps.LatLngBounds();
//// Creating an array that will contain the addresses
var places = [];
// Creating a variable that will hold the InfoWindow object
var infowindow;
// create this to add the marker Cluster on map
mc = new MarkerClusterer(map);
var popup_content = [];
var geocoder = new google.maps.Geocoder();
// image for ballon i want to change default ballon to this
var iconimage = "http://chart.apis.google.com/chart?cht=mm&chs=24x32&chco=FFFFFF,008CFF,000000&ext=.png";
var markers = [];
// Create this function for passing the values which was taken by webservice cntName is the return in webservice
function onSucess(cntName){
// loop through the cntName to pass the individual City one by one from geocode
for (i = 0; i < cntName.length; ++i) {
//for fixing the issue use closure to localize the cntName[i] variable before passing into geocode and callback function within it.
(function CreateMarkAndInfo(address) {
geocoder.geocode({ 'address': address },
function (results, status) {
if (status == google.maps.GeocoderStatus.OK) {
places[i] = results[0].geometry.location;
var marker = new google.maps.Marker({
position: places[i],
title: results[0].formatted_address,
map: map,
icon: iconimage
});
markers.push(marker);
mc.addMarker(marker);
google.maps.event.addListener(marker, 'click', function () {
if (!infowindow) {
infowindow = new google.maps.InfoWindow();
}
// Setting the content of the InfoWindow afterward
infowindow.setContent(popup_content[i]);
// Tying the InfoWindow to the marker afterward
infowindow.open(map, marker);
});
// Extending the bounds object with each LatLng
bounds.extend(places[i]);
// Adjusting the map to new bounding box
map.fitBounds(bounds);
// Zoom out after fitBound
var listener = google.maps.event.addListenerOnce(map, "idle", function () {
if (map.getZoom() < 10) map.setZoom(2);
});
}
else {
// if geocode will end the limit then make delay by timer in order to avoid the OVER_QUERY_LIMIT
if (status == google.maps.GeocoderStatus.OVER_QUERY_LIMIT) {
setTimeout(function () { CreateMarkAndInfo(address); }, (15)); // here i think i should use better approch but for now it`s ok.
}
else {
alert("Geocode was not successful for the following reason: " + status);
}
}
});
})(cntName[i]);// End closure trick
}
}
}
google.maps.event.addDomListener(window, 'load', InitializeMap);
Edit:
#just.another.programmer i cant because there is no latitute and longitude in DB, client will add cities and countries by him self thats why i had to convet city and country names by geocode and geocode doing it`s job accuretly here
How i am calling the City and country Names by web service
[System.Web.Services.WebMethod]
[System.Web.Script.Services.ScriptMethod()]
public static string[] GetCitiesbyUser_Extender()
{
System.Data.DataSet dtst = new System.Data.DataSet();
string ses = HttpContext.Current.Session["UserName"].ToString();
USTER.Dal.clsSearch clssearch = new USTER.Dal.clsSearch();
// Assinging the Stroed Procedure Method to DataSet
dtst = clssearch.GetAllCitiesByUser(ses);
string[] cntName = new string[dtst.Tables[0].Rows.Count];
int i = 0;
try
{
foreach (System.Data.DataRow rdr in dtst.Tables[0].Rows)
{
// Columns Name in SQL Server Table "CityName" and "CountryName"
cntName.SetValue(rdr["CityName"].ToString() +","+ rdr["CountryName"].ToString() , i);
i++;
}
}
catch { }
finally
{
}
return cntName;
}

Geocode your addresses one time when you first get them, then store the lat/long in your db so you don't have to geocode again. This will dramatically reduce your geocode requests and remove the need for setTimeout.

Place search request giving inconsistent results using bounds

As per this link: http://code.google.com/apis/maps/documentation/javascript/places.html#place_search_requests
The method can take either
-a point and a radius or
-a rectangle boundary
using the point + radius gives me correct results, however the max radius is only 50 km and I need my search to be up to 1000 km, so I tried using bounds.
When my bounds are small I get the same correct results as the point + radius, however when I increase the bounds I get no results at all.
The code below will give correct results, however if you replace the var sw and var ne with the commented out coordinates, it no longer works.
ie. kitchener is found within the boundary between ayr and guelph, but not in the boundary between detroit and ottawa. Which doesn't make any sense if you look at the map.
<script type="text/javascript">
var map;
var infowindow;
function initialize() {
var Cambridge = new google.maps.LatLng(43.346528, -80.417962);
var sw = new google.maps.LatLng(43.292501,-80.543175); // 41.914541,-83.282318
var ne = new google.maps.LatLng(43.605057,-80.156250); // 45.580391,-76.283051
var zoneBounds = new google.maps.LatLngBounds(sw,ne);
map = new google.maps.Map(document.getElementById('map'), {
mapTypeId: google.maps.MapTypeId.ROADMAP,
center: Cambridge,
zoom: 10
});
var request = {
bounds: zoneBounds,
//location: Cambridge, //using location and
//radius: 500000, //radius works
name: ['Kitchener, ON']
};
infowindow = new google.maps.InfoWindow();
var service = new google.maps.places.PlacesService(map);
service.search(request, callback);
}
function callback(results, status) {
if (status == google.maps.places.PlacesServiceStatus.OK) {
for (var i = 0; i < results.length; i++) {
createMarker(results[i]);
}
}
}
function createMarker(place) {
var placeLoc = place.geometry.location;
var marker = new google.maps.Marker({
map: map,
position: place.geometry.location
});
google.maps.event.addListener(marker, 'click', function() {
infowindow.setContent(place.name);
infowindow.open(map, this);
});
}
google.maps.event.addDomListener(window, 'load', initialize);
</script>
I'm supposed to be able to use PlacesServiceStatus to find the status of the request, i assume this would give me insight into the problem but I have no idea how to retrieve the status codes
Any help with this would be much appreciated
Thanks!
edit: ok, I added alert(status); and the status says it's "ZERO_RESULTS"

In the callback method you could do something like
function callback(results, status) {
window.alert(results.length);
that will tell you how many results you have, you could loop round them something like this...
for (var i = 0; i < results.length; i++) {
window.alert(results[i].formatted_address);
}
I've tried this myself and yes, if the bounds are greater than 50km then the results are pretty useless. I could guess at an answer; if the bounds are very large then it may involve too much of a hit on the Google servers. However, I don't like that answer so if someone knows better; help us out!
Another alternative is to use the Places Autocomplete -
https://developers.google.com/maps/documentation/javascript/places#places_autocomplete
You could use the geolocation but I doubt that will provide the responses you're looking for, for example if you geocode 'enfield' it will show you all the enfields in the world, if you geocode 'enf' it will show you a finish airport!

Google Maps API - multiple info windows and automatic centering

I've been cobbling together various bits of code from around the internet (including StackOverflow) and I've got a working map (almost) which geocodes postcodes from an array and creates infowindows for each one.
Two problems:
1) my info windows, which should take their text from another array, always use the last array value
2) i can't get the map to center automatically. I'm using a bit of code which has worked in other circumstances, but it doesn't in my code.
The code is fairly self-explanatory:
var geocoder = new google.maps.Geocoder();
var map = new google.maps.Map(document.getElementById('map'), {
//zoom: 10,
//center: new google.maps.LatLng(-33.92, 151.25),
mapTypeId: google.maps.MapTypeId.ROADMAP
});
var postcodes = [
"EH14 1PR",
"KY7 4TP",
"IV6 7UP"
];
var descriptions = [
"Slateford",
"Cortachy",
"Marybank"
];
var markersArray = [];
var infowindow = new google.maps.InfoWindow();
var marker, i, address, description;
for(var i = 0; i < postcodes.length; i++) {
address = postcodes[i];
description = descriptions[i];
geocoder.geocode(
{
'address': address,
'region' : 'uk'
},
function(results, status){
if (status == google.maps.GeocoderStatus.OK) {
marker = new google.maps.Marker({
position: results[0].geometry.location,
map: map
});
markersArray[i] = marker;
console.log(markersArray[i]);
google.maps.event.addListener(marker, 'click', (function(marker, i) {
return function() {
infowindow.setContent(description);
infowindow.open(map, marker);
}
})(marker, i));
} else {
alert("Geocode was not successful for the following reason: " + status);
return false;
}
}
);
var bounds = new google.maps.LatLngBounds();
$.each(markersArray, function (index, marker) {
bounds.extend(marker.position);
});
map.fitBounds(bounds);
console.log(bounds);
}
Any thoughts? The issue seems to be with the value of the counter i inside the geocode function.
Any help much appreciated!

1) my info windows, which should take their text from another array,
always use the last array value
2) i can't get the map to center automatically. I'm using a bit of
code which has worked in other circumstances, but it doesn't in my
code.
1) Yes this is a closure issue. This is how I get around it.
I create an object to store all of the properties I will be using. In your example I am going to use the postcode and the description.
function location(postalcode, desc){
this.PostalCode = postalcode;
this.Description = desc;
}
Now do a quick loop to add all the location objects to an array.
var locations = [];
for(var i = 0; i < postcodes.length; i++) {
locations.push(new location(postcodes[i], descriptions[i]));
}
Extract the geocode functionality into its own function with a parameter to take a location object. Then you can loop through the location object array and geocode each individually. So now both the post code and description are in scope when the request is built and sent.
function GeoCode(singleLocation){
geocoder.geocode(
{
'address': singleLocation.PostalCode,
'region' : 'uk'
},
function(results, status){
if (status == google.maps.GeocoderStatus.OK) {
var marker = new google.maps.Marker({
position: results[0].geometry.location,
map: map
});
//quick and dirty way
bounds.extend(marker.position);
map.fitBounds(bounds);
markersArray[i] = marker;
console.log(markersArray[i]);
google.maps.event.addListener(marker, 'click', function() {
infowindow.setContent(singleLocation.Description);
infowindow.open(map, this); //this refers to the marker
});
} else {
alert("Geocode was not successful for the following reason: "
+ status);
return false;
}
}
);
}
2) As you can see above the quick an dirty way to do this is extend and fit the bounds inside of the callback function for the geocode. This causes the fitBounds function to be called multiple times and isnt really a big deal if you only have a few markers, but will cause problems if you have hundreds or thousands of markers. In that case the right-way to do this is to create an async loop function. You can see an example of it on one of my previous answers.
Here is a functioning example of the code based on your example.

Two problems:
1) my info windows, which should take their text from another array,
always use the last array value
2) i can't get the map to center automatically. I'm using a bit of
code which has worked in other circumstances, but it doesn't in my
code.
Answers:
1) This is because most likely you have a closure issue here.
2) center will define the center point of your map, but in your code you have commented this
//center: new google.maps.LatLng(-33.92, 151.25),
removing the comment for this line will center to map to latitude of -33.92 and longitude of 151.25.
Use below:
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 10,
center: new google.maps.LatLng(-33.92, 151.25),
mapTypeId: google.maps.MapTypeId.ROADMAP
});