Not able to access html file in xamarin using GetManifestResourceStream

Question

I want to use leaflet map kit in xamarin.forms uwp project. For that I have created index.html file in pcl project. But when I'm trying to read that file it always returns null.

index.html

<!DOCTYPE html>
<html>
<head>
    <title>LeafletMap</title>

    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />

    <!--leaflet js-->
    <script src="JS/leaflet.js"></script>
    
    <!--leaflet css-->
    <link rel="stylesheet" href="CSS/leaflet.css" />
   
    <style>
        html, body {
            height: 100%;
            margin: 0;
        }

        #map {
            width: 600px;
            height: 400px;
        }
    </style>

    <style>
        body {
            padding: 0;
            margin: 0;
        }

        #map {
            height: 100%;
            width: 100vw;
        }
    </style>

</head>
<body>
    <div id='map'></div>

    <script type="text/javascript">

        var mbAttr = '&copy; <a href="http://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors',
            mbUrl = 'http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png',
            mbUrl2 = 'http://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/{z}/{y}/{x}',
            mbAttr2 = 'Tiles &copy; Esri &mdash; Source: Esri, i-cubed, USDA, USGS, AEX, GeoEye, Getmapping, Aerogrid, IGN, IGP, UPR-EGP, and the GIS User Community';

       var OSM = L.tileLayer(mbUrl, { id: 'OSM', attribution: mbAttr }),
           Sat = L.tileLayer(mbUrl2, { id: 'Sat', attribution: mbAttr2 });

       var baseLayers = {
            "OSM": OSM,
            "Satellite": Sat
       };
        
       var markerGroup = new L.LayerGroup();

        // Map initialization
        var map = L.map('map',{
            center: [-2.1319654, -79.9319396],
            zoom:5,
            layer: [OSM]
        });

        map.addLayer(markerGroup);

        L.control.layers(baseLayers).addTo(map);

       
    </script>
    
</body>
</html>

InitializeMap

var source = new HtmlWebViewSource();
source.BaseUrl = DependencyService.Get<IBaseUrl>().Get();
var assembly = typeof(MainPage).GetTypeInfo().Assembly;
var stream = assembly.GetManifestResourceStream("LeafletMap.index.html");

StreamReader reader = null;
if (stream != null) 
{
    try
    {
        reader = new StreamReader(stream);
        source.Html = reader.ReadToEnd();
    }
    catch (Exception ex)
    {
        System.Diagnostics.Debug.WriteLine($"Exception \n - {ex.Message}");
    }
    finally 
    {
        if (reader != null) 
        {
            reader.Dispose();
        }
    }
    webView.Source = source;
}

This line always returns null.

assembly.GetManifestResourceStream("LeafletMap.index.html");

Anyone know how to use leaflet mapkit in xamarin.forms?

I have referred this sample: https://github.com/osekom/LeafletMapXamarinForms.

It's working fine as it has old versioned xamarin.forms the same is not working with latest version.

is the file an Embedded Resource? Have you verified that you are using the correct resource id? — Jason, Dec 23 '21 at 17:50
Yes, I have set the action type to Embedded Resource. Correct resource id means? — Divyesh, Dec 23 '21 at 17:52
the resource id is the string you use to load the resource. You should be able to look at the properties in VS to see the ID — Jason, Dec 23 '21 at 17:57
Does this answer your question? [Can't load a manifest resource with GetManifestResourceStream()](https://stackoverflow.com/questions/3068736/cant-load-a-manifest-resource-with-getmanifestresourcestream) — ToolmakerSteve, Dec 23 '21 at 19:36
@Jason, unfortunately, for an embedded file, its properties only lists the filename and path - there is no "resource ID" property to show the string needed to get as resource. (This must have changed; I remember editing a resource ID there, in the past.) — ToolmakerSteve, Dec 23 '21 at 19:56

score 1 · Accepted Answer · answered Dec 23 '21 at 19:46

It worked in original because LeafletMap is the assembly name. Presumably, your project has a different name, e.g. MyProject.

Change

assembly.GetManifestResourceStream("LeafletMap.index.html");

To

assembly.GetManifestResourceStream("MyProject.index.html");

Substitute your actual project's Assembly Name for "MyProject". By default, this will be the same as the project's name. If in doubt, open "Properties" for project, Application tab, "Assembly name:".

If still doesn't work, here is how to see all the resource ids of your assembly:

var names = System.Reflection.Assembly.GetExecutingAssembly().GetManifestResourceNames();

Put a breakpoint on a line after this. Then in VS "Immediate" window, type "names".

I have updates in my post, can you check and let me know if you have some idea regards it? — Divyesh, Dec 24 '21 at 12:59

Not able to access html file in xamarin using GetManifestResourceStream

index.html

InitializeMap

This line always returns null.

Anyone know how to use leaflet mapkit in xamarin.forms?

1 Answers1