multiCheckbox questions do not render in Preview

[gracepotma]

To reproduce:

• Use this JSON file: https://docs.google.com/document/d/1qnYYCQdkZcql1wOtttZxSdlY_VKYTEK2xOSgbq11Q3Q/edit
• Apply this in the Form Builder
• Try changing the last Urine section question from Radio to multiCheckbox (e.g. Crystals type in urine sediment by light microscopy test) - this is a good example of a question that could have multiple true answers.
• Notice the question no longer shows up in the preview mode.

[denniskigen]

multiCheckbox questions don't render because that rendering type is not known to the form engine. It only knows how to render checkbox fields. This is a two-pronged problem because:

• Currently, the forms built using the form builder get rendered in O3 via the Angular form engine. The Angular form engine knows how to render multiCheckbox fields whereas the Form Builder does not. This means that if you have a multiCheckbox field in your schema, it won't render in the Form Builder preview, but will render fine in the reference application using the Angular form engine.

• In lieu of the above, whatever solution we adopt would have to take into account the fact that forms built using the Angular form engine use multiCheckbox whereas those built using the React form engine use checkbox, and that these fields are expected to work in the same way using both form engines. We shouldn't require users to amend their forms to account for this mismatch.