不支持驾驶旅行模式时的虚线路线

Question

我正在试图为我的地图制作离子路线，而且当驾驶的旅行模式不可用时，我似乎找不到将路线显示为点线的方法 - 就像在Google地图上一样。

这就是我的地图路线的样子： without the dotted route ->

这就是谷歌地图路线的样子： with the dotted route ->

这就是路线的代码现在的样子：

    function route(travel_mode, directionsService, directionsDisplay) {
    console.log($scope.transfer.origin.place_id, $scope.transfer.destination.place_id);
    if (!$scope.transfer.origin.place_id || !$scope.transfer.destination.place_id) {
      return;
    }
    else if (ok == 0) {
      ok = 1;
      directionsService.route({
        origin: {
          'placeId': $scope.transfer.origin.place_id
        }
        , destination: {
          'placeId': $scope.transfer.destination.place_id
        }
        , travelMode: travel_mode
      }, function (response, status) {
        if (status === 'OK') {
          directionsDisplay.setDirections(response);
          var origin1 = $scope.transfer.origin.place_title;
          var destinationA = $scope.transfer.destination.place_title;
          console.dir(origin1);
          var service = new google.maps.DistanceMatrixService();
          service.getDistanceMatrix({
            origins: [origin1]
            , destinations: [destinationA]
            , travelMode: 'DRIVING'
            , unitSystem: google.maps.UnitSystem.METRIC
          }, callback);
          function callback(response, status) {
            console.dir(response);
            if (status == 'OK') {
              origins = response.originAddresses[0];
              destinations = response.destinationAddresses[0];
              results = response.rows[0].elements[0];
              distance = results.distance.text;
              duration = results.duration.text;
              DTransfer.setData('distance', distance);
              DTransfer.setData('duration', duration);
            }
          }
        }
        else {
          window.alert('Directions request failed due to ' + status);
        }
      });
    }
  }
}

如果有任何修复，有人可以帮忙吗？