An unhandled exception occurred when using Bootswatch Theme

[tranpl]

Upgrading from 3.4.3 does not run into this issue. New installation of 4.0.5, downloaded the bootswatch collection in theme manager, set to Flatly theme, restart application. Getting error below:

An unhandled exception occurred while processing the request. NullReferenceException: Object reference not set to an instance of an object. Oqtane.Themes.Controls.LanguageSwitcher.OnParametersSet() in LanguageSwitcher.razor, line 32

Stack Query Cookies Headers Routing NullReferenceException: Object reference not set to an instance of an object. Oqtane.Themes.Controls.LanguageSwitcher.OnParametersSet() in LanguageSwitcher.razor + MenuAlignment = DropdownAlignment.ToLower() == "right" ? "dropdown-menu-end" : string.Empty; Microsoft.AspNetCore.Components.ComponentBase.CallOnParametersSetAsync() Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync() Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewComponentFrame(ref DiffContext diffContext, int frameIndex) Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewSubtree(ref DiffContext diffContext, int frameIndex) Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InsertNewFrame(ref DiffContext diffContext, int newFrameIndex) Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(ref DiffContext diffContext, int oldStartIndex, int oldEndIndexExcl, int newStartIndex, int newEndIndexExcl) Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.ComputeDiff(Renderer renderer, RenderBatchBuilder batchBuilder, int componentId, ArrayRange oldTree, ArrayRange newTree) Microsoft.AspNetCore.Components.Rendering.ComponentState.RenderIntoBatch(RenderBatchBuilder batchBuilder, RenderFragment renderFragment, out Exception renderFragmentException) Microsoft.AspNetCore.Components.RenderTree.Renderer.ProcessRenderQueue() Microsoft.AspNetCore.Components.RenderTree.Renderer.ProcessRenderQueue() Microsoft.AspNetCore.Components.RenderTree.Renderer.AddToRenderQueue(int componentId, RenderFragment renderFragment) Microsoft.AspNetCore.Components.ComponentBase.StateHasChanged() Oqtane.App.ChangeState(PageState pageState) in App.razor + StateHasChanged(); Oqtane.UI.SiteRouter.Refresh() in SiteRouter.razor + OnStateChange?.Invoke(_pagestate); Oqtane.UI.SiteRouter.OnParametersSetAsync() in SiteRouter.razor + await Refresh(); Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task) Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync() Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState) Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState) Microsoft.AspNetCore.Components.RenderTree.Renderer.gProcessAsynchronousWork|48_0() Microsoft.AspNetCore.Components.RenderTree.Renderer.WaitForQuiescence() Microsoft.AspNetCore.Components.RenderTree.Renderer.RenderRootComponentAsync(int componentId, ParameterView initialParameters) Microsoft.AspNetCore.Components.Rendering.HtmlRenderer.RenderComponentAsync(Type componentType, ParameterView initialParameters) Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext+<>c11+<b11_0>d.MoveNext() Microsoft.AspNetCore.Mvc.ViewFeatures.StaticComponentRenderer.PrerenderComponentAsync(ParameterView parameters, HttpContext httpContext, Type componentType) System.Threading.Tasks.ValueTask.get_Result() Microsoft.AspNetCore.Mvc.ViewFeatures.ComponentRenderer.PrerenderedServerComponentAsync(HttpContext context, ServerComponentInvocationSequence invocationId, Type type, ParameterView parametersCollection) Microsoft.AspNetCore.Mvc.ViewFeatures.ComponentRenderer.RenderComponentAsync(ViewContext viewContext, Type componentType, RenderMode renderMode, object parameters) System.Threading.Tasks.ValueTask.get_Result() Microsoft.AspNetCore.Mvc.TagHelpers.ComponentTagHelper.ProcessAsync(TagHelperContext context, TagHelperOutput output) Microsoft.AspNetCore.Razor.Runtime.TagHelpers.TagHelperRunner.gAwaited|0_0(Task task, TagHelperExecutionContext executionContext, int i, int count) Oqtane.Pages.PagesHost.b14_1() in _Host.cshtml +

Microsoft.AspNetCore.Razor.Runtime.TagHelpers.TagHelperExecutionContext.SetOutputContentAsync() Oqtane.Pages.Pages__Host.ExecuteAsync() in _Host.cshtml +

Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageCoreAsync(IRazorPage page, ViewContext context) Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageAsync(IRazorPage page, ViewContext context, bool invokeViewStarts) Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderAsync(ViewContext context) Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ViewContext viewContext, string contentType, Nullable statusCode) Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ViewContext viewContext, string contentType, Nullable statusCode) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|30_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResultExecutedContextSealed context) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.ResultNext(ref State next, ref Scope scope, ref object state, ref bool isCompleted) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|28_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|25_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Logged|17_1(ResourceInvoker invoker) Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Logged|17_1(ResourceInvoker invoker) Microsoft.AspNetCore.Routing.EndpointMiddleware.g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger) Swashbuckle.AspNetCore.SwaggerUI.SwaggerUIMiddleware.Invoke(HttpContext httpContext) Swashbuckle.AspNetCore.Swagger.SwaggerMiddleware.Invoke(HttpContext httpContext, ISwaggerProvider swaggerProvider) Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context) Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context) Oqtane.Infrastructure.JwtMiddleware.Invoke(HttpContext context) in JwtMiddleware.cs + } Oqtane.Infrastructure.TenantMiddleware.Invoke(HttpContext context) in TenantMiddleware.cs + } Microsoft.AspNetCore.Localization.RequestLocalizationMiddleware.Invoke(HttpContext context) Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddlewareImpl.Invoke(HttpContext context) Show raw exception details

[sbwalker]

@leigh-pointer it looks like the recent fix to the LanguageSwitcher is not backward compatible:

Object reference not set to an instance of an object. Oqtane.Themes.Controls.LanguageSwitcher.OnParametersSet() in LanguageSwitcher.razor, line 32 MenuAlignment = DropdownAlignment.ToLower() == "right" ? "dropdown-menu-end" : string.Empty;

This is because DropdownAlignment is null - so the ToLower() will throw an exception

[leigh-pointer]

@sbwalker

Upgrading from 3.4.3 does not run into this issue. New installation of 4.0.5

LanguageSwitcher changes are not in release 4.0.5. It is an issue with the https://github.com/oqtane/oqtane.theme.bootswatch Theme

[sbwalker]

@leigh-pointer the error message in the original post clearly contains a reference to "MenuAlignment = DropdownAlignment.ToLower() == "right" ? "dropdown-menu-end" : string.Empty;" which only exists in the Dev branch. So the issue is not in the 4.0.5 release - it is in the Dev branch (which is still versioned 4.0.5).