Javascript Pass Parameter to Callback or Set Variable Value in DistanceMatrixStatus

Question

I have been playing a little bit with Google\'s DistanceMatrixService. The code below works, but, how can I pass another parameter to the callback function or grab one of th

Answer 1

You can't change how Google calls the callback, but you can let it call your own locally function as the callback and then have that (via a closure) call another callback after adding the desired extra argument like this:

function GoogleMapDistance(YourLatLong,DestLatLong, item)
{
    var service = new google.maps.DistanceMatrixService();
    service.getDistanceMatrix(
    {
    origins: [YourLatLong],
    destinations: [DestLatLong],
    travelMode: google.maps.TravelMode.DRIVING,
    unitSystem: google.maps.UnitSystem.IMPERIAL,
    avoidHighways: false,
    avoidTolls: false
    }, function(response, status) {callback(response, status, item)});
}

Or, you could just define your callback inline so it has access to the parent function variables directly:

function GoogleMapDistance(YourLatLong,DestLatLong, item)
{
    var service = new google.maps.DistanceMatrixService();
    service.getDistanceMatrix(
    {
    origins: [YourLatLong],
    destinations: [DestLatLong],
    travelMode: google.maps.TravelMode.DRIVING,
    unitSystem: google.maps.UnitSystem.IMPERIAL,
    avoidHighways: false,
    avoidTolls: false
    }, function callback(response, status)
    {
        // you can access the parent scope arguments like item here
        if (status == google.maps.DistanceMatrixStatus.OK)
        {
        var origins = response.originAddresses;
        var destinations = response.destinationAddresses;
          for (var i = 0; i < origins.length; i++)
          {
              var results = response.rows[i].elements;
              for (var j = 0; j < results.length; j++)
              {
                  var element = results[j];
                  var from = origins[i];
                  var to = destinations[j];
                  var distance = element.distance.text;
                  var duration = element.duration.text;
                  var ResultStr = distance + "  (" + duration + ")";
              }
          }
        document.getElementById("Results1").innerHTML = ResultStr;
        }
    }

)}