Peewee inline models do not get created

[forshev]

Thanks for your great work on Flask-Admin!

When i add a new inline model instance, then save, the page reloads and nothing happens, no flashes, errors, etc., view's create_model/update_model method is not called so new record is not inserted into the DB.
I presume this is because of required hidden input, which holds id value for existing records but for new records it has no value so form validation error happens.

[cslanziano]

I had a similar problem. As you said the problem is a required hidden input, with name = 'id' that it is empty for new records. After try several things I found a simple solution: set the default value of that field to some number.

class MyModelView(ModelView):
    inline_models = [(db.Model, dict(form_args = dict(id = dict(default = 4))))]

Edit:

The above solution works, but sometimes when try to add a new record in a 'edition view' depending of the default value, it collides with a old record id, then the submit updates the old record and does not create a new one. A solution is use zero as default value to avoid the collision.

class MyModelView(ModelView):
    inline_models = [(db.Model, dict(form_args = dict(id = dict(default = 0))))]

Another solution is set the field as optional using the Optional validator (from wtforms).

from wtforms.validators import Optional

class MyModelView(ModelView):
    inline_models = [(db.Model, dict(form_args = dict(id = dict(validators = [Optional()]))))]