I have
x_trainer_id = fields.Many2one('res.partner', string='Trainer')
field, and I want to filter data in it by the value that is put in category_id tag field in partner form.
I want to show just those records in it their category_id tag value is defined Trainer.
If i understand this correct, try to define you field in your view like:
<field name="x_trainer_id" domain="[('category_id','=',category_id[0][2])]" />
The field category_id has to be defined in that view, too. But if you extend the res.partner views, there shouldn't be any problem.
try this way in python:
x_trainer_id = fields.Many2one(comodel_name='res.partner', string='Trainer',domain=lambda self: [('category_id.name', '=', 'Trainer')])
pass domain=lambda self: [('category_id.name', '=', 'Trainer')]
