[va-checkbox] - Add Indeterminate State - Development

[danbrady]

Description

In USWDS 3.8.0, the checkbox has a new indeterminate state. We should bring this capability into VADS. See #3365 (comment) for information on the preliminary accessibility revie and implementing this.

Estimating

Provide your estimate of 1, 2, 3, 5, 8 or 13
@Andrew565 - 3
@ataker -
@harshil1793 -
@it-harrison - 3
@jamigibbs - 3
@micahchiang -
@powellkerry - 3
@rmessina1010 -
@rsmithadhoc - 3

Tasks

• Review DST backlog for outstanding issues with this component, if necessary
• Create web component and add to Storybook
• Write any necessary tests
• Add Chromatic link to #[add accessibility ticket number] and request review from an accessibility specialist
• Contact designer for design review
• Display the appropriate maturity scale option in Storybook (once this feature is available)
  • If this is a new component that has not gone through Staging Review, it should be labeled "Use with Caution: Candidate"
• Merge component
• Create a new release of component-library
• Update component-library dependency in vets-design-system-documentation to get the updated component-docs.json
• Add analytics set-up to vets-website repository. See guidance here.

Acceptance Criteria

• Component is written and added to Storybook
• Component has had accessibility and design reviews
• Design.va.gov has the latest version of component-library
• Analytics has been configured for the component in the vets-website repo

[caw310]

Hey team! Please add your planning poker estimate with Zenhub @Andrew565 @ataker @harshil1793 @it-harrison @jamigibbs @micahchiang @nickjg231 @powellkerry @rmessina1010 @rsmithadhoc

[jamigibbs]

I just want to mention that we need to make sure we do an accessibility audit of this feature. There appears to be a number of different ways screen readers interact with the indeterminate state and we might find some challenges with that.

I also couldn't find an example on the USWDS site of this implemented so it's difficult to check it before we start dev.

cc @rsmithadhoc

[jamigibbs]

Linking to the related ticket for updating to USWDS v3.8.0:

• Update component-library to USWDS 3.8.0 (if possible 3.8.1) #2612

[danbrady]

I also couldn't find an example on the USWDS site of this implemented so it's difficult to check it before we start dev.

If it helps a11y testing or dev, the USWDS Indeterminate checkbox is in their storybook.

[caw310]

Ticket for a11y review for this. #3351

[caw310]

Added this a11y audit ticket which we will work on before development of this.