Hi, I updated my code.

what if they are related fields from a different model?

Hi, In your case, based on fieldA , the other two fields are displaying. account.voucher.line is the One2many to account.voucher ,

You can have related field only in account.voucher.line and not in account.voucher

For example,

class AccountVoucher(models.Model):

_inherit = "account.voucher"

fieldB = fields.Char(string="Field B")

fieldC = fields.Char(string="Field C")

class AccountVoucherLine(models.Model):

_inherit = "account.voucher.line"

fieldA = fields.Selection([

('field1', 'Field 1'),

('field2', 'Field 2'),

], 'Field Type', required=True, index=True)

fieldB = fields.Char(string="Field B", related='voucher_id.fieldB', store=True)

fieldC = fields.Char(string="Field C", related='voucher_id.fieldC', store=True)

and as I answered before, view can be written only for account.voucher.line