How to deal with related and computed fields in Transient Models in Odoo 8?

Question

I have a problem which I am not able to understand. I have added two new fields to the model stock.production.lot. These fields are computed floats, and work perfect. Their names are current_qty and expected_qty.

Then, I have created a Transient Model. In this one, I created a many2one field lot_id which points to the model stock.production.lot. And I have added two float fields, also named current_qty and expected_qty, which are related to the respective ones I mentioned above.

The problem is that only current_qty is getting the right value (the other one gets always zero).

Example:

I create a lot. When I do this, current_qty is computed and values 10.000, and expected_qty is computed too and values 5.000.

Now I open the Transient Model, and current_qty gets 10.000, which is right, but expected_qty gets False. Why?

Even I have added other field to the Transient Model. This one is a computed char which should show the next: current_qty (expected_qty), following the values of this example, it should be 10.000 (5.000). But it also takes False value (it does not write the current_qty neither). Besides, I write log messages inside the compute method to check if the method is called and which values it takes. And surprisingly, the values of current_qty and expected_qty shown in the log are right! (10.000 and 5.000).

Python code

class ProductLotAvailable(models.TransientModel):
    _name = 'product.lot.available'

    @api.multi
    @api.depends('current_qty', 'expected_qty')
    def _compute_beautiful_qty(self):
        for available_lot in self:
            current_qty = str(available_lot.current_qty)
            _logger.info(current_qty)
            expected_qty = str(available_lot.expected_qty)
            _logger.info(expected_qty)
            available_lot.beautiful_qty = current_qty + '(' + expected_qty + ')'

    lot_id = fields.Many2one(
        comodel_name='stock.production.lot',
        string='Lot',
        readonly=True,
    )
    current_qty = fields.Float(
        related='lot_id.current_qty',
        string='Current lot quantity',
        readonly=True,
        digits=dp.get_precision('Product Unit of Measure'),
    )
    expected_qty = fields.Float(
        related='lot_id.expected_qty',
        string='Expected lot quantity',
        readonly=True,
        digits=dp.get_precision('Product Unit of Measure'),
    )
    beautiful_qty = fields.Char(
        compute='_compute_beautiful_qty',
        string='Current lot quantity',
        readonly=True,
    )

XML code

<field name="product_lots_available" nolabel="1">
    <tree create="false" delete="false" editable="bottom">
        <field name="current_qty" invisible="0"/>
        <field name="expected_qty" invisible="0"/>
        <field name="beautiful_qty"/>
        <field name="lot_id"/>
    </tree>
</field>

Can anyone help me with this? It is possible that there is a simple error in my code which I was not able to see for the last hours.

Emipro Technologies Pvt. Ltd. Emipro Technologies Pvt. Ltd. · Accepted Answer · 2016-10-25T04:17:48

The only reason what I am thinking is because it's related fields, so the value in that field will be placed only after you save that record. And because this model is transient model so wizard is getting opened but you can't open the same record again to verify that result.

To verify it if go to the database and check the record you will get the value there. For double sure just keep those both fields functional Store=False, so value will always be there.

I didn't found any other problem in your code.

How to deal with related and computed fields in Transient Models in Odoo 8?

2 Answers