Question

I am trying to display Google Maps inside a Partial View with JSON. I have already tried the code inside a normal view and it works perfectly fine.

I have the following:-

Partial View ShowMap.cshtml

@using Microsoft.Web.Helpers

<script src="~/Scripts/jquery-1.8.3.min.js"></script>
<div class="experienceRestrictedText">
    @Maps.GetGoogleHtml("1, Redmond Way, Redmond, WA", width: "400", height: "400")
</div>

Index.cshtml (where the Partial view is launched)

    $('.modal_link_map').on('click', function (e) {
        $('.modal_part').show();
        var id = $(this).attr('data-id');
        var context = $('#tn_select').load('/Experience/ShowMap?id=' + id, function () {
            initSelect(context);
        });
        e.preventDefault();
        return false;
    });

And the controller Action is as follows:-

        public ActionResult ShowMap()
        {
        _ItemID = Convert.ToInt32(Request.QueryString["id"]);

        viewModel.ExperienceViewModel.Experience =     unitOfWork.ExperienceRepository.GetByID(_ItemID);

        return PartialView(viewModel);
        }

Do I need to include anything else for this map to work?

Answer 1

I am not familiar with the @Maps.GetGoogleHtml helper but I am afraid that somehow this helper is including the following script:

<script src="//maps.google.com/maps/api/js?sensor=false" type="text/javascript"></script>

Except that this script cannot be loaded asynchronously because it uses document.write() to load the actual API. To make this work you should specify a callback parameter. Here’s how your partial could look like:

<div class="experienceRestrictedText">
    <script src="//maps.google.com/maps/api/js?sensor=false&callback=initialize" type="text/javascript"></script>
    <script type="text/javascript">
        function initialize() {
            var map = new google.maps.Map(document.getElementById("map"), { zoom: 14, center: new google.maps.LatLng(47.652437, -122.132424), mapTypeId: google.maps.MapTypeId['ROADMAP'] });
            new google.maps.Geocoder().geocode({ address: '1, Redmond Way, Redmond, WA' }, function (response, status) {
                if (status === google.maps.GeocoderStatus.OK) {
                    var best = response[0].geometry.location;
                    map.panTo(best);
                    new google.maps.Marker({ map: map, position: best });
                }
            });
        }
    </script>
    <div class="map" id="map" style="width:400px; height:400px;"></div>
</div>

Notice how a callback parameter is passed to the http://maps.google.com/maps/api/js script and the actual initialization of the maps is done inside this callback.

Also notice that I have removed the jquery script from the partial. I guess that jQuery is already loaded in your layout because you seem to be using it to attach to a .on() handler.

As an alternative you could have included the <script src="//maps.google.com/maps/api/js?sensor=false" type="text/javascript"></script> in your main view but once you load the partial, the
@Maps.GetGoogleHtml helper would have included it a second time.

Personally I am not a big fan of those kind of helpers because they are completely obscuring the underlying calls leaving you without much control and understanding of what’s happening.