Routing to a selected language returns a blank page!

Hi

I've applied this topic for multilingual in mvc core 2.2 web app.:

https://medium.com/swlh/step-by-step-tutorial-to-build-multi-cultural-asp-net-core-web-app-3fac9a960c43

The example above is applied for none mvc core web app and I applied it for mvc one.

firstly, I Installed the required packages:

<PackageReference Include="LazZiya.ExpressLocalization" Version="4.0.0" /><PackageReference Include="LazZiya.TagHelpers" Version="4.0.1" />

Then I created new folder 'LocalizationResources' with two new classes in it:

    public class ExpressLocalizationResource
    {
    }

    public class ViewLocalizationResource
    {
    }

Then created a source file ViewLocalizationResource.ar.resx inside ViewLocalizationResource class with some strings:

Then configured Startup.cs:

public void ConfigureServices(IServiceCollection services)
{
    //Some code
            var cultures = new[]
            {
                new CultureInfo("tr"),
                new CultureInfo("ar"),
                new CultureInfo("hi"),
                new CultureInfo("en"),
            };
            services.AddMvc()
                 .AddExpressLocalization<ExpressLocalizationResource, ViewLocalizationResource>(
                 ops =>
                 {
                     ops.ResourcesPath = "LocalizationResources";
                     ops.RequestLocalizationOptions = o =>
                     {
                         o.SupportedCultures = cultures;
                         o.SupportedUICultures = cultures;
                         o.DefaultRequestCulture = new RequestCulture("en");
                     };
                 })
                 .SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
             //Some code

            app.UseRequestLocalization();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });

Then _ViewImports.cs:

@using MultiLang
@using MultiLang.Models
@addTagHelper *, Microsoft.AspNetCore.Mvc.TagHelpers

@using System.Globalization

@addTagHelper *, LazZiya.TagHelpers
@addTagHelper *, LazZiya.ExpressLocalization

Then added the method to HomeController:

        public IActionResult SetCultureCookie(string cltr, string returnUrl)
        {
            Response.Cookies.Append(
                CookieRequestCultureProvider.DefaultCookieName,
                CookieRequestCultureProvider.MakeCookieValue(new RequestCulture(cltr)),
                new CookieOptions { Expires = DateTimeOffset.UtcNow.AddYears(1) }
            );

            return LocalRedirect(returnUrl);
        }

Then added the rtl.css and ltr.css to css folder then updated shared _Layout:

@using System.Globalization
@{
    var culture = CultureInfo.CurrentCulture.Name;
    var dirCss = CultureInfo.CurrentCulture.TextInfo.IsRightToLeft ? "rtl" : "ltr";
}

    @*Some Code*@

    <link rel="stylesheet" href="~/css/site.css" /><link rel="stylesheet" href="@($"/css/{dirCss}.css")" />

    @*Some Code*@

                    <partial name="_LoginPartial" /><language-nav cookie-handler-url="@Url.Action("SetCultureCookie", "Home", new { area="", cltr="{0}", returnUrl="{1}" })"></language-nav>

Then localized Home/Index view:

<div class="text-center"><h1 class="display-4" localize-content>Welcome</h1><p localize-content>Learn about</p></div>

for now every thing is working fine but when I firstly run the app. it is shown sometimes in Arabic and sometimes in English with successfully localized content according to the language.

Then if I navigate to any language of the four langauges, the page is shown blank with the two letters at the last of the url for example '/ar'.

Why? and How to solve please?