Toolkit Basemap Gallery doesn't display the Thumbnails properly

[LuisRguezEsriSpain]

I am developing an application with MAUI.

• Product: ArcGIS Maps SDK for .NET
• Version: 200.2
• Project template: ArcGIS Maps SDK .NET MAUI App (Esri)
• Framework: .NET 7.0
• Toolkit Basemap Gallery widget

When I run de app by using "Samsung Galaxy Tab A SM-T510" and "Samsung Galaxy Tab A SM-T580", Toolkit Basemap Gallery widget doesn't display the Thumbnails properly.

After creating a Esri Case, Esri recommend me submit a new Issue.

[dotMorten]

@LuisRguezEsriSpain Would you be able to share a small sample that reproduces the issue?

[LuisRguezEsriSpain]

I share a small sample.

PoCDrones.zip

[dotMorten]

Thank you. Were you only seeing this on Android, or only on certain Android devices? I see the basemaps both on Windows and on my Android:

[LuisRguezEsriSpain]

Hi Morten,

I only see Thumbnails on certain Android devices.

Por example:

• I see Thumbnails on mobiles Miui 10 and Samsung Galaxy A52s
• I don't see Thumbnails on tablets "Samsung Galaxy Tab A SM-T510" and "Samsung Galaxy Tab A SM-T580"

[dotMorten]

It looks like it is hitting this fallback:

arcgis-maps-sdk-dotnet-toolkit/src/Toolkit/Toolkit.Maui/BasemapGallery/ByteArrayToImageSourceConverter.cs

Line 34 in 8e5bc02

return ImageSource.FromResource("Esri.ArcGISRuntime.Toolkit.Maui.Assets.BasemapLight.png", typeof(BasemapGallery).Assembly); ;

That data should be coming from here:

arcgis-maps-sdk-dotnet-toolkit/src/Toolkit/Toolkit/UI/Controls/BasemapGallery/BasemapGalleryItem.cs

Line 100 in 8e5bc02

private async Task LoadImage()

Since I can't reproduce, would you be able to debug what is happening on your specific Android devices and see why the thumbnails fail to load?

[LuisRguezEsriSpain]

Hi Morten,

This is the debug's result.

at RuntimeCoreNet.GeneratedWrappers.CoreImage.GetEncodedBuffer() at Esri.ArcGISRuntime.UI.RuntimeImage.GetEncodedBufferAsync(CancellationToken cancellationToken) at PoCDrones.BasemapGallery.BasemapGalleryItem.LoadImage() in C:\LuisRodriguez\Proyectos\ENAIRE\200_2\Incidencia\PoCDrones\PoCDrones\BasemapGallery\BasemapGalleryItem.cs:line 107

this.Thumbnail.Source.AbsoluteUri: "https://www.arcgis.com/sharing/rest/content/items/983b312ebd9b4d15a02e00f50acdb1c1/info/thumbnail/thumbnail1607564423352.jpeg"

[dotMorten]

Thank you for the detailed screenshots. InvalidProgramException sounds like something went wrong in .NET or the compilation: https://learn.microsoft.com/en-us/dotnet/api/system.invalidprogramexception?view=net-7.0
Is your .NET up to date? Any chance you could also try with the latest .NET 8?

[LuisRguezEsriSpain]

Hi Morten,

I don't see how to create a ArcGIS Maps SDK .NET MAUI project using .NET.

I also don't see a way to change an existing project's .NET Framework.

[dotMorten]

.NET 8 shipped as final yesterday. If you update your visual studio to latest, you should now see it in your dropdown (before this you needed the preview release)

[LuisRguezEsriSpain]

Hi Morten,

I've installed the latest versión of visual studio.

I've also installed ArcGIS_Maps_SDK_DotNet_Templates_200_3_0.vsix.

In project propertiens I cannot choose either "Target Android Framework" or "Minimum Target Android Framework".

In addition to this issue I have others issues:

• When I change content of appicon.svg and appiconfg.svg I get this error when the project is built.

• In Android app I cannot see svg icons as souce if ImageButton
• In Android app I cannot change IsEnabled property of "Frame" Maui controls by code

[dotMorten]

@LuisRguezEsriSpain are you able to build a normal .NET MAUI app targeting .NET 8? Most of the settings you refer too are easiest set in the .csproj file directly.

[LuisRguezEsriSpain]

@dotMorten I've done this workaround in BasemapGalleryItem class and work properly:

    private async Task LoadImage()
    {
        IsLoadingThumbnail = true;
        try
        {
            await (Thumbnail?.LoadAsync() ?? Task.CompletedTask);

            if (Thumbnail?.LoadStatus == LoadStatus.Loaded)
            {
                var stream = await Thumbnail.GetEncodedBufferAsync();
                var buffer = new byte[stream.Length];
                await stream.ReadAsync(buffer, 0, (int)stream.Length);
                ThumbnailData = buffer;

#if WINDOWS_XAML
ThumbnailBitmap = await Thumbnail.ToImageSourceAsync();
#endif
}
_hasLoaded = true;
}
catch (Exception ex)
{
await LoadImageAux();
}
finally
{
IsLoadingThumbnail = false;
}
}

    private async Task LoadImageAux()
    {
        try
        {
            HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, Thumbnail.Source);
            HttpClient client = new HttpClient(new HttpClientHandler());
            var response = await client.SendAsync(request, HttpCompletionOption.ResponseHeadersRead).ConfigureAwait(false);
            var content = response.EnsureSuccessStatusCode();
            var streamRes = await content.Content.ReadAsStreamAsync();
            byte[] buffer = new byte[16 * 1024];
            using (MemoryStream ms = new MemoryStream())
            {
                int read;
                while ((read = await streamRes.ReadAsync(buffer, 0, buffer.Length)) > 0)
                {
                    ms.Write(buffer, 0, read);
                }
                ThumbnailData = ms.ToArray();
            }
        }
        catch (Exception ex2)
        {
        }
    }