I want to create an account.invoice.line object from code, with only providing the product_id (which is loaded from sale.config.settings), the quantity (it will be always 1.0) and the price_unit, also the invocie_id (that was previously created).

In old api i used to call onchange methods pasing fields as parameters so i created the lines with the values returned with the onchange updating only certain values i wanted, but i cannot manage to do this with the new api.

Can i call the onchange pasing needed parameters to get the needed data, as for example account_id?