Javascript Closure with google.maps.Geocoder::geocode

问题

I'm using google.maps javascript API v3. I need to translate a set of civic addresses to markers on a google map with 'click' listeners. When the user clicks on the marker in the map, I want another window to open with a url related to that address (another tab would be ideal).

I can't manage to keep the relation between the address and the url, because I'm using javascript Closure with the google method geocode().

I have a set of addresses such as

var addresses = [ '123 street street', '124 street street' ];  
var urls = [ 'www.example.com/1', 'www.example.com/2' ];

Then I use the API to geocode and create markers on the map

for (var i = 0; i<addresses.length; i++)
{
    var address = addresses[i];
    var url = urls[i];
    geocoder.geocode(
        { 'address' : address },
    function(result, status) {
       var x = url // url == ""

       var marker = new google.maps.Marker({
          position: result[0].geometry.location,
          map: map,
          title:"Test"
       });

       google.maps.event.addListener(marker, 'click', function(event){
          alert(url);
          window.open(url);
       },false);
    }
}

inside the anonymous function, how can I use var url ?

回答1:

It seems that the solution was to split everything in separate functions.

function showAddress() {

    //geocoder = new Geocoder();

    for (var i = 0; i<addresses.length; i++)
    {
        var address = addresses[i];
        var url = urls[i];

        findAddress(address,url);
        pausecomp(400);
      }
}

function findAddress(address,url)
{
    geocoder.geocode(
        { 'address' : address },
        function(result, status) {
            var marker;
            if(status == google.maps.GeocoderStatus.OK) {
                marker = new google.maps.Marker({
                    position: result[0].geometry.location,
                    map: map,
                    title:"Longueuil"
                });

            }
            attachUrl(marker, url);
        }
    );
}

function attachUrl(marker, url)
{
    google.maps.event.addListener(marker, 'click', function(event){
        alert(url);
        window.open(url);
    },false);
}

My guess is that function calls create persistent copies of the values held by the variables and not merely pointers to them.

来源：https://stackoverflow.com/questions/6171664/javascript-closure-with-google-maps-geocodergeocode

标签

javascript

google-maps

closures

google-maps-markers

geocode