Odoo 11 Development Essentials - Third Edition

Specific purpose decorators

A few other decorators have more specific purposes and are to be used together with the decorators described earlier:

• @api.depends(fld1,...) is used for computed field functions, to identify on what changes the (re)calculation should be triggered. It must set values on the computed fields, otherwise it will error.
• @api.constrains(fld1,...) is used for validation functions, and performs checks for when any of the mentioned fields are changed. It should not write changes in the data. If the checks fail, an exception should be raised.
• @api.onchange(fld1,...) is used in the user interface, to automatically change some field values when other fields are changed. The self argument is a singleton with the current form ...