javascript - Google Maps v3 directionsRenderer.setMap(null) not working to clear previous directions -

i trying clear previous directions google map. when search, polyline , markers previous search still show. have tried using directionsrenderer.setmap(null), doesn't make difference. ideas i'm doing wrong?

(function () {         maps.directions = function(googlemap, data, options) {         var directionsservice = new google.maps.directionsservice(),             directionsrenderer = new google.maps.directionsrenderer();          function getdirections() {             directionsservice.route(data.request, function(response, status) {                 if (status === google.maps.directionsstatus.ok) {                     directionsrenderer.setdirections(response);                 }             });         }         directionsrenderer.setmap(null);         directionsrenderer.setmap(googlemap);         getdirections();     }; })(); 

this because initializing new directionsrenderer in every call of function.

make directionsrenderer little more global. , first setmap(null), initialize, setmap(googlemap)

like this:

(function () {        var directionsrenderer;     maps.directions = function(googlemap, data, options) {         if(directionsrenderer){             directionsrenderer.setmap(null);         }         var directionsservice = new google.maps.directionsservice();          directionsrenderer = new google.maps.directionsrenderer();         function getdirections() {             directionsservice.route(data.request, function(response, status) {                 if (status === google.maps.directionsstatus.ok) {                     directionsrenderer.setdirections(response);                 }             });         }          directionsrenderer.setmap(googlemap);         getdirections();     }; })();