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Implementation of uPlot on Blazor WASM

See original GitHub issue

I’ve been trying to implement uPlot on Blazor for a while now. Sadly I had no luck. I am not a professional programmer by any means. I’m very new to JS and I’ve been getting the following error when I run the application:

crit: Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
  Unhandled exception rendering component: then is not a function
  TypeError: then is not a function
      at new uPlot (https://localhost:44326/dist/uPlot.iife.js:3902:7)
      at generateUPlot (https://localhost:44326/js/MuPlot.js:48:10)
      at https://localhost:44326/_framework/blazor.webassembly.js:1:3942
      at new Promise (<anonymous>)
      at Object.beginInvokeJSFromDotNet (https://localhost:44326/_framework/blazor.webassembly.js:1:3908)
      at Object.w [as invokeJSFromDotNet] (https://localhost:44326/_framework/blazor.webassembly.js:1:64006)
      at _mono_wasm_invoke_js_blazor (https://localhost:44326/_framework/dotnet.5.0.1.js:1:190800)
      at do_icall (<anonymous>:wasm-function[10596]:0x194e58)
      at do_icall_wrapper (<anonymous>:wasm-function[3305]:0x79df9)
      at interp_exec_method (<anonymous>:wasm-function[2155]:0x44ad3)
Microsoft.JSInterop.JSException: then is not a function
TypeError: then is not a function
at new uPlot (https://localhost:44326/dist/uPlot.iife.js:3902:7)
at generateUPlot (https://localhost:44326/js/MuPlot.js:48:10)
at https://localhost:44326/_framework/blazor.webassembly.js:1:3942
at new Promise (<anonymous>)
at Object.beginInvokeJSFromDotNet (https://localhost:44326/_framework/blazor.webassembly.js:1:3908)
at Object.w [as invokeJSFromDotNet] (https://localhost:44326/_framework/blazor.webassembly.js:1:64006)
at _mono_wasm_invoke_js_blazor (https://localhost:44326/_framework/dotnet.5.0.1.js:1:190800)
at do_icall (<anonymous>:wasm-function[10596]:0x194e58)
at do_icall_wrapper (<anonymous>:wasm-function[3305]:0x79df9)
at interp_exec_method (<anonymous>:wasm-function[2155]:0x44ad3)
at Microsoft.JSInterop.JSRuntime.<InvokeAsync>d__15`1[[System.Object, System.Private.CoreLib, Version=5.0.0.0, 
Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
at Microsoft.JSInterop.JSRuntimeExtensions.InvokeVoidAsync(IJSRuntime jsRuntime, String identifier, Object[] args)
at Blazor5.Pages.Visualizer.DrawMuGraph() in 
C:\\Visualizer.razor:line 84
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle)

I honestly haven’t figured out the exact issue yet. I would greatly appreciate it if I could have some help or pointers!

Issue Analytics

State:
Created 3 years ago
Comments:5 (3 by maintainers)

Top GitHub Comments

1reaction

leeoniyacommented, Dec 10, 2020

TypeError: then is not a function

i’m guessing whatever you’re passing as the third argument to the uPlot constructor is neither a dom element, nor a callable function, so it’s crashing here with the assumption that it’s a function:

https://github.com/leeoniya/uPlot/blob/a91bdcecae048a805f8e8be7a139f260dad065f1/src/uPlot.js#L2316

0reactions

leeoniyacommented, Dec 17, 2020

gonna close this, since i think that’s all that needs to be done on the uPlot side, but feel free to ask more questions here, if needed.