How to refresh google maps by event using jquery gmap library

Question

i want to refresh my maps when user set lat and long in input box. but when users sets another lat, the maps still show the first one.

<script type="text/javascript">
$(document).ready(function(){
 $(document).on("click", "#generate", function() {
    var Lattitude = $('#Lattitude').val();
  var Longitude = $('#Longitude').val();
  google.maps.event.trigger(('#map_canvas'), 'resize'); //is it right code to refresh my map?
  var map = $('#map_canvas').gmap().bind('init', function(ev, map) {
   if (Lattitude == "" || Longitude=="") {
    var address = $('#merchantAddress').val();
    var key = '...';
    var url = 'https://maps.googleapis.com/maps/api/geocode/json?address='+address+'&key='+key;
    $.get(url, function( results ) {
         if (results.status == 'OK') {
          Lattitude = results.geometry.location.lat;
        Longitude = results.geometry.location.lng;
        $('#map_canvas').gmap('addMarker', {'position': Lattitude+','+Longitude, 'bounds': true, 'zoom':5}).click(function() {
       $('#map_canvas').gmap('openInfoWindow', {'content': 'Your Location'}, this);
      });
       }else{
        alert (results.status);
       }
    });
   }else{
    $('#map_canvas').gmap('addMarker', {'position': Lattitude+','+Longitude, 'bounds': true}).click(function() {
     $('#map_canvas').gmap('openInfoWindow', {'content': 'Your Location'}, this);
    });
   }
  });
  $('#map_canvas').removeClass("hide");
 });
});

</script>