google geocoder service - google-maps

I'm trying to use Google geocoder service to get the coordinates of cities input by the user. However looks like there's some problem initializing the LatLng() object (latlngCity), and the map won't show up. The code is as following:
var map;
var latlngCity;
function initialize() {
var geocoder = new google.maps.Geocoder();
geocoder.geocode({'address': 'Lisbon, PT'}, function(results, status) {
if(status == google.maps.GeocoderStatus.OK) {
latlngCity = results[0].geometry.location;
}
});
var myMapOptions = {
zoom: 8,
center: latlngCity,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
map = new google.maps.Map(document.getElementById("map_canvas"),
myMapOptions);
}
For simplicity, I'm inserting the address city string myself. Variables map and latlngCity are globals. Is there anything wrong with this code?
Thanks very much.

You need to move the map creation code into the geocode callback (or alternatively create the map with some default position and then re-center the map inside the callback).
In your code, latlngCity is undefined by the time of map creation while geocode is still being executed (asynchronously).
Hope this makes sense. Otherwise I'll provide some code. Let me know.

Related

Geocode to produce multiple markers google maps

Can any suggest why this code doesn't provide 2 markers on my map?
http://pastebin.com/1uaNjeVy
I'm not sure whether it is a syntax error or a restriction by google?
Edit:
I got it working by doing the below anyway, apologies for not posting the code direct to here.
My new issue is that when I open the page sometimes it finds all of the addresses, other times it brings up the alert?
var geocoder = new google.maps.Geocoder();
geocoder.geocode( {'address': "Eldon Square 24-26 Sidgate, Newcastle upon Tyne"}, function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
var img = "https://dl.dropboxusercontent.com/u/55888592/marker26.png";
var info = "<div><p>Sometext</p></div>";
var infowindow = new google.maps.InfoWindow({
});
var latlng = results[0].geometry.location;
var marker = new google.maps.Marker({
icon: img,
position: latlng,
map: map,
content: info
});
google.maps.event.addListener(marker, "click", function(content) {
infowindow.setContent(this.content);
infowindow.open(map,this);
});
} else {alert("alert");
}
marker.setMap(map);
});
The geocoder is asynchronous. Your are setting the marker map variable before the marker is created. You should do that in the callback function of the geocoder. (The javascript console is your friend)
And your marker images fail to load from the URL provided (probably because it is https)
working example

Is it possible get a place object with specific lat and lng?

I am not sure my question is valid. But I have some requirement like below.
Is it possible get a place object with specific lat and lng?
In details when we use autocomplete method we can get the place object like: "place = autocomplete.getPlace();".
Is it possible to call getPlace() method for specific lat and lng or any other solution available?
To be precise, what you're asking is called Reverse Geocoding.
Wiki:
Reverse geocoding is the process of back (reverse) coding of a point
location (latitude, longitude) to a readable address or place name.
Yes Google provides reverse geocoding service. But it is not a single line which you mentioned in your question.
It has its own procedure.
Check Google's Reverse Geocoding for more information.
You may find the below code useful.
var geocoder;
var map;
function initialize() {
geocoder = new google.maps.Geocoder(); // * initialize geocoder class
var latlng = new google.maps.LatLng(40.730885,-73.997383);
var mapOptions = {
zoom: 8,
center: latlng,
mapTypeId: 'roadmap'
}
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
}
function getPlace() {
var lat = your Latitude; // give valid lat
var lng = your Longitude; // give valid lng
var latlng = new google.maps.LatLng(lat, lng);
geocoder.geocode({'latLng': latlng}, function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
if (results[1]) {
map.setZoom(11);
marker = new google.maps.Marker({
position: latlng,
map: map
});
}
else {
//handle error status accordingly
}
}
}
}
google.maps.event.addDomListener(window, 'load', initialize);
Hope your understand.

Google Maps v3, reverse Geocoding and multiple Infowindow

I'm working on a google map v3.
On this map I want display several markers each one with its Infowindow where shows some information about that point.
The source of information is an javascript array with some data for each point, and up here everything works fine.
The array contains (SOMETIMES) the address (sometimes null) and ALWAYS lat-long coordinates, so when the address isn't present I have to make a reverse-geocoding. Here my code:
var geocoder = new google.maps.Geocoder();
for(var i=0;i<markersArray.length;i++){
var la=markersArray[i][0]);
var lo=markersArray[i][1]);
gpoint=new google.maps.LatLng( la,lo);
var aMarker = new MarkerWithLabel({ //part of Google Maps Utility Lib
position: gpoint,
map: map,
labelContent: deviceID,
labelAnchor: new google.maps.Point(22, 0),
labelClass: "labelStyle",
html: "<ul><li>Speed: "+markersArray[i][3]+"</li></ul>",
address: markersArray[i][4]
});
if (aMarker.address<="" || aMarker.address==null) {
geocoder.geocode({'latLng': gpoint}, function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
if (results[1]) {
aMarker.address=results[1].formatted_address;
}
}
});
}
google.maps.event.addListener(aMarker, 'click', function () {
infowindow.setContent(this.html+" "+this.address);
infowindow.open(map, this);
});
....
}
Almost everything is ok: the markers are in position and all them show the right infowindow with the right addresses except those where the addresses were empty and were reverse-geocoding.
For this last set only the last one marker infowindow shows the right address, all other infowindow addresses's are empty.
Any idea?
Very thanks!
One way to fix this is to create a function which does the reverse geocoding and can have function closure on the infowindow and the marker.
As the reverse geocode operation is asynchronous, the returned address isn't available for any except the last marker.

Is it possible to display the map with only the address?

I would like to use GoogleMaps API v3.
Before, I was using version n°2 and I had just to put the address and the map was displayed.
Is it always possible with version n°3 ?
If yes, how ?
I always find scripts with latitude, longitude... but no script with address.
Thanks a lot and sorry for my poor english.
I guess you mixed up Maps-Javascript-API and the Static-Maps-API(current Version is V2).
In the static-maps-API you may use an address as center-parameter.
In the Javascript-APIs you need a LatLng (no matter if V2 or V3). If you only have an adress, you must request the LatLng using a geocode-request.
Basically you need to look for something called geocode. It is a part of API documentation. something like below will help:
var geocoder;
var map;
function initialize() {
geocoder = new google.maps.Geocoder();
var latlng = new google.maps.LatLng(-34.397, 150.644);
var myOptions = {
zoom: 8,
center: latlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
}
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);
}
});
}
Helpful Link

Getting Address from Google Map (Reverse Geocoding)

I have a online shop and people buy products and we send a products to their address , but sometimes customers enter a bad address and we couldn't find the destination.
I want to show a Google map in address form then customer locate their address on the map and finally address of that point fetched from Google map.
Is Google offers this feature?
You can also check the address against known deliverable addresses within the area. This database is maintained by the USPS, who visits (practically) every address every single weekday. Using a web-based API you could query the database and either get an automatic match or get a list of suggested matches. I know this doesn't provide you a map, but in many cases, it can allow your clients to correct their address right there on the spot and can be very easy to implement and use. Some services offer a Javascript implementation as well as an XML hook into the API. If you're googling it, look for address verification webservice, or something similar.
I work for an address verification service called smartystreets.
Yes, this service is known as reverse geocoding.
And it's actually quite simple to implement. Assuming you get lat and long values from map click event, like so:
var map;
function initialize() {
var myLatlng = new google.maps.LatLng(-25.363882,131.044922);
var myOptions = {
zoom: 4,
center: myLatlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
google.maps.event.addListener(map, 'click', function(event) {
getAddress(event.latLng);
});
}
function getAddress(location latlng) {
var geocoder;
var map;
var infowindow = new google.maps.InfoWindow();
var marker;
function initialize() {
geocoder = new google.maps.Geocoder();
var myOptions = {
zoom: 8,
center: latlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
}
}
Take a look at reverse geocoding.Although your question is many questions in one and you should break it to smaller ones and ask them here also.