# Trait Error: The 'children' trait of a VBox instance ...

**URL:** https://discourse.itk.org/t/trait-error-the-children-trait-of-a-vbox-instance/5416
**Category:** Beginner Questions
**Created:** [October 14, 2022, 4:02pm UTC](https://discourse.itk.org/t/trait-error-the-children-trait-of-a-vbox-instance/5416 "2022-10-14T16:02:22Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Kevin\_Sweeney](https://discourse.itk.org/user_avatar/discourse.itk.org/kevin_sweeney/32/2947_2.png) [@Kevin\_Sweeney](https://discourse.itk.org/u/Kevin_Sweeney)
#### Post date: [October 14, 2022, 4:02pm UTC](https://discourse.itk.org/t/trait-error-the-children-trait-of-a-vbox-instance/5416/1 "2022-10-14T16:02:22Z")

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I am getting the error:  
`TraitError: The 'children' trait of a VBox instance contains an Instance of a TypedTuple which expected a Widget, not the Viewer at '0x2aaab5d0ad00'.`

when running the code below in Jupyter Lab

```auto
import itkwidgets
import ipywidgets
    
view = itkwidgets.view(geometries=None, background=[0.0, 0.0, 0.0])

# Headings
heading = ipywidgets.HTML(value="<h1>Heading</h1>")

# Output Widget
widget = ipywidgets.VBox(children = [heading, view])

```

Below are my versions of packages.

> itkwidgets 1.0a16 pypi\_0 pypi  
> ipywidgets 7.6.5 pyhd3eb1b0\_1 defaults

When running this locally with

> itkwidgets 0.32.0 py38h32f6830\_0 conda-forge

this error does not occur. I needed to update to latest `itkwidgets` version due to issue with widgets not showing in Jupyter Lab. How can I fix this issue.

Not sure if it matters, but in my application, I will be updating the `geometries` variable often.

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### Author: ![dzenanz](https://discourse.itk.org/user_avatar/discourse.itk.org/dzenanz/32/1093_2.png) [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [October 14, 2022, 8:45pm UTC](https://discourse.itk.org/t/trait-error-the-children-trait-of-a-vbox-instance/5416/2 "2022-10-14T20:45:47Z")

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@PaulHax might be able to help.

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### Author: ![PaulHax](https://discourse.itk.org/user_avatar/discourse.itk.org/paulhax/32/2949_2.png) [@PaulHax](https://discourse.itk.org/u/PaulHax)
#### Post date: [October 14, 2022, 9:11pm UTC](https://discourse.itk.org/t/trait-error-the-children-trait-of-a-vbox-instance/5416/3 "2022-10-14T21:11:06Z")

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Seems with the 1.X version of itkwidgets is not a Widget, probably by design/not-gotten-around-to-it. Deep insight, I know. I would open a question/feature-request issue at:

> **[GitHub - InsightSoftwareConsortium/itkwidgets: Interactive Jupyter widgets to...](https://github.com/InsightSoftwareConsortium/itkwidgets)**
>
> Interactive Jupyter widgets to visualize images, point sets, and meshes in 2D and 3D - GitHub - InsightSoftwareConsortium/itkwidgets: Interactive Jupyter widgets to visualize images, point sets, an...

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### Author: ![Kevin\_Sweeney](https://discourse.itk.org/user_avatar/discourse.itk.org/kevin_sweeney/32/2947_2.png) [@Kevin\_Sweeney](https://discourse.itk.org/u/Kevin_Sweeney)
#### Post date: [October 17, 2022, 7:56am UTC](https://discourse.itk.org/t/trait-error-the-children-trait-of-a-vbox-instance/5416/4 "2022-10-17T07:56:34Z")

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Thanks for that @PaulHax. I have opened an issue ([Trait Error: The ‘children’ trait of a VBox instance ... itkwidgets 1.0a16 · Issue #556 · InsightSoftwareConsortium/itkwidgets · GitHub](https://github.com/InsightSoftwareConsortium/itkwidgets/issues/556)).  
Would I be able to wrap this viewer in an `Output` or something to be able to get a work around?