pos/pos_tare/models/pos_config.py

from odoo import api, models, fields


class PosConfig(models.Model):
    _inherit = "pos.config"

    iface_tare_method = fields.Selection(
        [
            ("manual", "Input the tare manually"),
            ("barcode", "Scan a barcode to set the tare"),
            ("both", "Manual input and barcode"),
        ],
        string="Tare Input Method",
        default="both",
        required=True,
        help="Select tare method:\n"
        "* 'manual' : the scale screen has an extra tare input field;\n"
        "* 'barecode' : (scan a barcode to tare the selected order line;\n"
        "* 'both' : manual input and barcode methods are enabled;",
    )

    iface_gross_weight_method = fields.Selection(
        [
            ("manual", "Input the Gross Weight manually"),
            ("scale", "Input Gross Weight via Scale")
        ],
        string="Gross Weight Input Method",
        default="scale",
        required=True,
    )

    iface_tare_uom_id = fields.Many2one(
        string="Unit of Measure of the tare",
        comodel_name="uom.uom",
        default=lambda s: s._default_iface_tare_uom_id(),
        required=True,
    )

    @api.model
    def _default_iface_tare_uom_id(self):
        return self.env.ref("uom.product_uom_kgm")