I'm trying to use the Google geocoder API V3 to plot a location on a map based on an address specified by the user, code is below.
When I make a request directly (e.g. to http://maps.googleapis.com/maps/api/geocode/json?address=peterborough&sensor=false) I get the expected response. However, when I make the same request using the code below, the midpoint variable is always undefined after the getLatLong function has exited.
What am I doing incorrectly?
function loadFromSearch(address)
{
midpoint = getLatLong(address);
mapCentre = midpoint;
map.setMapTypeId(google.maps.MapTypeId.ROADMAP);
...
}
function getLatLong(address)
{
var result;
var url = 'http://maps.googleapis.com/maps/api/geocode/json?address=' + encodeURIComponent(address) + '&sensor=false'
$.getJSON(url,
function (data){
if (data.status == "OK")
{
result = data.results[0].geometry.location;
}
});
return result;
}
==================================================================================
In light of responses, I have now updated the code to the following. I'm still not getting any result though, with breakpoints set in Firebug the result = data.results[0].geometry.location; never gets hit.
function loadFromSearch(address)
{
midpoint = getLatLong(address, loadWithMidpoint);
}
function getLatLong(address, callback)
{
var result;
var url = 'http://maps.googleapis.com/maps/api/geocode/json?address=' + encodeURIComponent(address) + '&sensor=false'
$.getJSON(url,{},
function (data) {
if (data.status == "OK")
{
result = data.results[0].geometry.location;
callback(result);
}
});
}
function loadWithMidpoint(centre)
{
mapCentre = centre;
map.setMapTypeId(google.maps.MapTypeId.ROADMAP);
...
}
=============================================================================
I have it! The final code, which works, looks like this:
function loadFromSearch(coordinates, address)
{
midpoint = getLatLong(address, latLongCallback);
}
function getLatLong(address, callback)
{
var geocoder = new google.maps.Geocoder();
var result = "";
geocoder.geocode({ 'address': address, 'region': 'uk' }, function (results, status) {
if (status == google.maps.GeocoderStatus.OK)
{
result = results[0].geometry.location;
latLongCallback(result);
}
else
{
result = "Unable to find address: " + status;
}
});
return result;
}
function latLongCallback(result)
{
mapCentre = result;
map.setMapTypeId(google.maps.MapTypeId.ROADMAP);
...
}
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