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MudExpansionPanel causes unhandled error

See original GitHub issue

This was reproduced with the following vanilla environement:

Using Visual Studio 2019, new Project and new Blazor WebAssembly project (.net 5).
Follow manual Install steps as per https://mudblazor.com/getting-started/installation

I have tried all the examples from the expansion panel. For example the first one:

<MudExpansionPanels>
    <MudExpansionPanel Text="Panel One" MaxHeight="150">
        Panel One Content
    </MudExpansionPanel>
    <MudExpansionPanel Text="Panel Two" MaxHeight="500">
        Panel Two Content
    </MudExpansionPanel>
    <MudExpansionPanel Text="Panel Three" MaxHeight="1000">
        Panel Three Content
    </MudExpansionPanel>
    <MudExpansionPanel Text="Panel Four">
        Panel Four Content
    </MudExpansionPanel>
</MudExpansionPanels>

The panel renders but without the child content. This causes the following unhandled error in the browser. It works fine on TryMudBlazor.

Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
      Unhandled exception rendering component: Could not find 'mudElementRef.getBoundingClientRect' ('mudElementRef' was undefined).
      Error: Could not find 'mudElementRef.getBoundingClientRect' ('mudElementRef' was undefined).
          at https://localhost:44311/_framework/blazor.webassembly.js:1:1287
          at Array.forEach (<anonymous>)
          at e.findFunction (https://localhost:44311/_framework/blazor.webassembly.js:1:1247)
          at b (https://localhost:44311/_framework/blazor.webassembly.js:1:2989)
          at https://localhost:44311/_framework/blazor.webassembly.js:1:3935
          at new Promise (<anonymous>)
          at Object.beginInvokeJSFromDotNet (https://localhost:44311/_framework/blazor.webassembly.js:1:3908)
          at Object.w [as invokeJSFromDotNet] (https://localhost:44311/_framework/blazor.webassembly.js:1:64232)
          at _mono_wasm_invoke_js_blazor (https://localhost:44311/_framework/dotnet.5.0.4.js:1:190800)
          at do_icall (<anonymous>:wasm-function[10596]:0x194e4e)
Microsoft.JSInterop.JSException: Could not find 'mudElementRef.getBoundingClientRect' ('mudElementRef' was undefined).
Error: Could not find 'mudElementRef.getBoundingClientRect' ('mudElementRef' was undefined).
    at https://localhost:44311/_framework/blazor.webassembly.js:1:1287
    at Array.forEach (<anonymous>)
    at e.findFunction (https://localhost:44311/_framework/blazor.webassembly.js:1:1247)
    at b (https://localhost:44311/_framework/blazor.webassembly.js:1:2989)
    at https://localhost:44311/_framework/blazor.webassembly.js:1:3935
    at new Promise (<anonymous>)
    at Object.beginInvokeJSFromDotNet (https://localhost:44311/_framework/blazor.webassembly.js:1:3908)
    at Object.w [as invokeJSFromDotNet] (https://localhost:44311/_framework/blazor.webassembly.js:1:64232)
    at _mono_wasm_invoke_js_blazor (https://localhost:44311/_framework/dotnet.5.0.4.js:1:190800)
    at do_icall (<anonymous>:wasm-function[10596]:0x194e4e)
   at Microsoft.JSInterop.JSRuntime.<InvokeAsync>d__15`1[[MudBlazor.Interop.BoundingClientRect, MudBlazor, Version=5.0.5.0, Culture=neutral, PublicKeyToken=null]].MoveNext()
   at MudBlazor.MudCollapse.UpdateHeight()
   at MudBlazor.MudCollapse.OnAfterRenderAsync(Boolean firstRender)
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle)

Issue Analytics

State:
Created 3 years ago
Comments:8 (4 by maintainers)

Top GitHub Comments

1reaction

mikes-ghcommented, Mar 15, 2021

I suggest you ask your peers for support on the discord #help channel. You could also compare one of our working templates with your code to see what is causing the issue in your setup. We try and keep the github issues for bugs and enhancements.

0reactions

attig78commented, Mar 15, 2021

ok thanks, will take it up in the Discord channel. Thanks for the help.

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