About how have field class take responsibility of setting initial value instead of the caller form

[rivernews]

About how to set Initial value

• We can specify initialValue when newing inputfieldprops with a initial = {...} arg.

Can we just use Formik's values and not passing a initialValue? One challenge is we need to populate existing values for update form.

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Components

• The application status form.

Two things:

1. Prepare intialValues and other stuff, and pass them to <FormFactory> as props.
2. Add fields to form by new FormFieldProps(fieldName, label, ...).

• The LinkField

Have no direct relation w/ initialValue. But LinkField contains the structure of the field and knows the key of the field in both values and initialValue.

LinkField can actually pass in a Link instance, so it works for both create & update form. Then store the initialValues in local. The form factory will have to access them from the LinkField instance. You can use a get function though.

• The form factory

Passes initialValue=this.props.intialValue on <Formik />. If we need to modify initialValue at the beginning only and don't need update ... we can still use local state as this.state.initialValue.

Also has the formFieldPropsList passed in. If initialValue info is there, we can append that to this.state = {initialValue: ... in constructor.

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Execution

Setup of initialValues will occur in LinkField (LinkFieldProps class, more precisely)

• [ ] Set initialValues in LinkField.
  • [ ] Make sure LinkField accepts a Link instance for update form to populate the correct initial values.
  • [ ] Use the Link instance to generate initialValues for LinkField
  • [ ] Write a public function in LinkFieldProps class for other components to access initialValues of this field. The caller will use initialValues = { ...LinkFieldProps.initialValues(), ... } to merge the form's initialValues together.
• [ ] application status form refactor to use LinkField
• [ ] In form factory, implement componentDidMount() and loop through this.props.FieldPropsList. If LinkFieldProps, then call .initialValues() to pull out initial values. Collect all initial values, and set local variables for <Formik initialValues={this.initialValues} /> .
• [ ] Test if initial value works for create form
• [ ] Test if work for update form

Originally posted by @rivernews in https://github.com/rivernews/appl-tracky-spa/issues/19#issuecomment-489365680

[rivernews]

We can't remember specific details of the issue. But if it starts causing an issue e.g. scalability, we can always look back.