I am trying to use Flask-Admin to create a create/edit form for the model Matriline shown below. This model has a string field name and a field pod_id with a foreign key constraint to another model Pod, which itself has a foreign key field to a Clan model.
The default form created by Flask-Admin shows the name field and a select field for the Pod instances, but I would like to add a field Clan, which would reset the Pod list according to the Clan instance selected.
To add the Clan field I override the default ModelView for Matriline and add an extra select field Clan with all the Clan instances, as shown in the view MatrilineView below.
Now I need to add some Ajax code to the rendered form to reset the list of pods every time a new clan is selected.
Do I have to replace entirely the default form by a custom one including the Ajax code? Or is there any easier way to that with Flask-Admin?
<b>models.py</b>
...
class Matriline(db.Model):
__tablename__ = 'matriline'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.Unicode(64))
pod_id = db.Column(db.Integer, db.ForeignKey('pod.id'))
def __unicode__(self):
return self.name
class Pod(db.Model):
__tablename__ = 'pod'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.Unicode(64))
matrilines = db.relationship('Matriline', backref='pod', lazy='select')
clan_id = db.Column(db.Integer, db.ForeignKey('clan.id'))
def __unicode__(self):
return self.name
class Clan(db.Model):
__tablename__ = 'clan'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.Unicode(64))
pods = db.relationship('Pod', backref='clan', lazy='select')
def __unicode__(self):
return self.name
...
<b>views.py</b>
from flask_admin.contrib import sqla
from wtforms import SelectField
from orcall import models
class MatrilineView(sqla.ModelView):
column_hide_backrefs = False
form_extra_fields = {
'clan': SelectField('Clan',
choices=[ (c.id, c.name) for c in models.Clan.query.all()])
}
column_list = ('name', 'pod', 'clan')
...
You are need to use a QuerySelectField. For example:
from flask.ext.admin.form import Select2Widget
class MatrilineView(sqla.ModelView):
column_hide_backrefs = False
form_extra_fields = {
'clan': sqla.fields.QuerySelectField(
label='Clan',
query_factory=lambda: Clan.query.all(),
widget=Select2Widget()
)
}
column_list = ('name', 'pod', 'clan')