How do I generate dynamic fields in WTForms

Question

I am trying to generate a form in WTForms that has dynamic fields according to this documentation http://wtforms.simplecodes.com/docs/1.0.2/specific_problems.html#dynamic-fo

Answer 1

This is how i got it to work.

class MyForm(FlaskForm):
    mylist = SelectField('Select Field', choices=[])

@app.route("/test", methods=['GET', 'POST']
def testview():
    form = MyForm()
    form.mylist.choices = [(str(i), i) for i in range(9)]

Strangely this whole thing stops working for me if i use coerce=int. I am myself a flask beginner, so i am not really sure why coerce=int causes issue.