38 lines
804 B
ReStructuredText
38 lines
804 B
ReStructuredText
.. _topics-fields_default_value:
|
|
|
|
=======================
|
|
Default value of fields
|
|
=======================
|
|
|
|
When a record is created, each field, which doesn't have a value specified,
|
|
is set with the default value if exists.
|
|
|
|
The following class method:
|
|
|
|
.. code-block:: python
|
|
|
|
Model.default_<field name>()
|
|
|
|
Return the default value for ``field name``.
|
|
|
|
This example defines an ``Item`` model which has a default ``since``:
|
|
|
|
|
|
.. code-block:: python
|
|
|
|
import datetime
|
|
|
|
from trytond.model import ModelView, ModelSQL, fields
|
|
|
|
|
|
class Item(ModelSQL, ModelView):
|
|
"Item"
|
|
__name__ = 'item'
|
|
since = fields.Date('since')
|
|
|
|
@classmethod
|
|
def default_since(cls):
|
|
return datetime.date.today()
|
|
|
|
See also method :meth:`~trytond.model.Model.default_get`.
|