Example of implementing a HasOne relationship through the Template field.
use MoonShine\UI\Fields\Template; //... protected function formFields(): iterable{ return [ Template::make('Comment') ->changeFill(fn (Article $data) => $data->comment) ->changePreview(fn($data) => $data?->id ?? '-') ->fields(app(CommentResource::class)->getFormFields()) ->changeRender(function (?Comment $data, Template $field) { $fields = $field->getPreparedFields(); $fields->fill($data?->toArray() ?? []); return Components::make($fields); }) ->onAfterApply(function (Article $item, array $value) { $item->comment()->updateOrCreate([ 'id' => $value['id'] ], $value); return $item; }) ];} //...