how to add class to label in quick_form flask bootstrap - python-2.7

Question

Using quick_form Flask-Bootstrap to generate the form is very convenient for me, however, I could not find in their documentation a way that I can add extras class to label as required by my template theme.
My forms.py class look like this:
from flask_wtf import Form
from wtforms import StringField,PasswordField,TextField,SubmitField
from wtforms.validators import InputRequired,EqualTo,Email,ValidationError
class Building_Form(Form):
BuildingName = TextField('Building Name')
BuildingType = TextField('Building Type')
FloorNums = TextField('Numers of Floor')
BuildUnits = TextField('Units in Building')
BuildSize = TextField('Building Size')
BuiltYear = TextField('Built in (year)')
BuildOpeningTime = TextField('Open Time')
BuildClosingTime = TextField('Close Time')
My routes.py is like following:
from app.import_core import *
from flask_wtf import FlaskForm
from wtforms import Form, BooleanField, StringField, PasswordField, validators
from wtforms.validators import DataRequired
from flask_wtf.file import FileField, FileRequired
from werkzeug.utils import secure_filename
from werkzeug.security import generate_password_hash, check_password_hash
from .forms import Building_Form
# from app.user.models import TBL_USER
import pdb
#app.route('/building')
def show_building_listing():
return render_template('building_listing.html')
#app.route('/builing/new',methods=['GET','POST'])
def add_new_builing():
form = Building_Form()
if request.method=='POST':
return '<h1>Ok Building added</h1>'
return render_template('new_building.html',form=form)
My new_building.html to render a form:
{% extends "__dashboard.html" %}
{% import "bootstrap/wtf.html" as wtf %}
{% block include_css %}
<link rel="stylesheet" href="{{url_for('static',filename='css/login.css')}}">
<link rel="stylesheet" href="{{url_for('static',filename='css/bt-social-button/bootstrap-social.css')}}">
{% endblock %}
{% block content %}
<div class="card">
<div class="card-body">
{{ wtf.quick_form(form, extra_classes='bmd-label-floating') }}
</div>
</div>
{% endblock %}
I would like to add classes bmd-label-floating to my form label however it ended up with those classes in <form> instead.
How can I add that class my labels? Thanks.

Answer 1

I had a similar problem. A list of items was used to generate a form with multiple checkboxes. I needed to add a label class for styling them horizontally. I was able to loop through my form object and change class for the form field.label.
<form action="" method="post">
{% with test = form.example %}
{% for field in test %}
{{ field.label(class_='checkbox-inline') }}
{{ field }}
{% endfor %}
{% endwith %}
<p>{{ form.submit() }}</p>
</form>