Django form – set label
Question:
I have a form that inherits from 2 other forms. In my form, I want to change the label of a field that was defined in one of the parent forms. Does anyone know how this can be done?
I’m trying to do it in my __init__
, but it throws an error saying that “‘RegistrationFormTOS’ object has no attribute ’email'”. Does anyone know how I can do this?
Thanks.
Here is my form code:
from django import forms
from django.utils.translation import ugettext_lazy as _
from registration.forms import RegistrationFormUniqueEmail
from registration.forms import RegistrationFormTermsOfService
attrs_dict = { 'class': 'required' }
class RegistrationFormTOS(RegistrationFormUniqueEmail, RegistrationFormTermsOfService):
"""
Subclass of ``RegistrationForm`` which adds a required checkbox
for agreeing to a site's Terms of Service.
"""
email2 = forms.EmailField(widget=forms.TextInput(attrs=dict(attrs_dict, maxlength=75)), label=_(u'verify email address'))
def __init__(self, *args, **kwargs):
self.email.label = "New Email Label"
super(RegistrationFormTOS, self).__init__(*args, **kwargs)
def clean_email2(self):
"""
Verifiy that the values entered into the two email fields
match.
"""
if 'email' in self.cleaned_data and 'email2' in self.cleaned_data:
if self.cleaned_data['email'] != self.cleaned_data['email2']:
raise forms.ValidationError(_(u'You must type the same email each time'))
return self.cleaned_data
Answers:
You access fields in a form via the ‘fields’ dict:
self.fields['email'].label = "New Email Label"
That’s so that you don’t have to worry about form fields having name clashes with the form class methods. (Otherwise you couldn’t have a field named ‘clean’ or ‘is_valid’) Defining the fields directly in the class body is mostly just a convenience.
You should use:
def __init__(self, *args, **kwargs):
super(RegistrationFormTOS, self).__init__(*args, **kwargs)
self.fields['email'].label = "New Email Label"
Note first you should use the super call.
It don’t work for model inheritance, but you can set the label directly in the model
email = models.EmailField("E-Mail Address")
email_confirmation = models.EmailField("Please repeat")
You can set label
as an attribute of field when you define form.
class GiftCardForm(forms.ModelForm):
card_name = forms.CharField(max_length=100, label="Cardholder Name")
card_number = forms.CharField(max_length=50, label="Card Number")
card_code = forms.CharField(max_length=20, label="Security Code")
card_expirate_time = forms.CharField(max_length=100, label="Expiration (MM/YYYY)")
class Meta:
model = models.GiftCard
exclude = ('price', )
Here’s an example taken from Overriding the default fields:
from django.utils.translation import ugettext_lazy as _
class AuthorForm(ModelForm):
class Meta:
model = Author
fields = ('name', 'title', 'birth_date')
labels = {
'name': _('Writer'),
}
help_texts = {
'name': _('Some useful help text.'),
}
error_messages = {
'name': {
'max_length': _("This writer's name is too long."),
},
}
Try on Models.py
email = models.EmailField(verbose_name="E-Mail Address")
email_confirmation = models.EmailField(verbose_name="Please repeat")
if all other solutions don’t work, this one worked for me (to change the user class label to django contrib auth)
#in models.py
User._meta.get_field('username').verbose_name = "new name"
While using a class’ constructor to change the field label for an instance works, it’s better from an object-oriented design standpoint to make the change at the class level if the label doesn’t need to be customized per-instance.
For example, the following will change the label on PasswordChangeForm‘s new_password2 field from "New password confirmation" to "Confirm Password":
class MyPasswordChangeForm(PasswordChangeForm):
PasswordChangeForm.base_fields['new_password2'].label = 'Confirm Password'
Take a look in django/forms/forms.py, you’ll see that DeclarativeFieldsMetaclass removes the fields from a class’ attribute list and places them in base_fields and declared_fields.
class Form(BaseForm, metaclass=DeclarativeFieldsMetaclass):
...
class DeclarativeFieldsMetaclass(MediaDefiningClass):
"""Collect Fields declared on the base classes."""
def __new__(mcs, name, bases, attrs):
# Collect fields from current class and remove them from attrs.
attrs['declared_fields'] = {
key: attrs.pop(key) for key, value in list(attrs.items())
if isinstance(value, Field)
}
new_class = super().__new__(mcs, name, bases, attrs)
# Walk through the MRO.
declared_fields = {}
for base in reversed(new_class.__mro__):
# Collect fields from base class.
if hasattr(base, 'declared_fields'):
declared_fields.update(base.declared_fields)
# Field shadowing.
for attr, value in base.__dict__.items():
if value is None and attr in declared_fields:
declared_fields.pop(attr)
new_class.base_fields = declared_fields
new_class.declared_fields = declared_fields
There’s a comment in BaseForm that provides further explanation:
class BaseForm:
...
# The base_fields class attribute is the *class-wide* definition of
# fields. Because a particular *instance* of the class might want to
# alter self.fields, we create self.fields here by copying base_fields.
# Instances should always modify self.fields; they should not modify
# self.base_fields.
I have a form that inherits from 2 other forms. In my form, I want to change the label of a field that was defined in one of the parent forms. Does anyone know how this can be done?
I’m trying to do it in my __init__
, but it throws an error saying that “‘RegistrationFormTOS’ object has no attribute ’email'”. Does anyone know how I can do this?
Thanks.
Here is my form code:
from django import forms
from django.utils.translation import ugettext_lazy as _
from registration.forms import RegistrationFormUniqueEmail
from registration.forms import RegistrationFormTermsOfService
attrs_dict = { 'class': 'required' }
class RegistrationFormTOS(RegistrationFormUniqueEmail, RegistrationFormTermsOfService):
"""
Subclass of ``RegistrationForm`` which adds a required checkbox
for agreeing to a site's Terms of Service.
"""
email2 = forms.EmailField(widget=forms.TextInput(attrs=dict(attrs_dict, maxlength=75)), label=_(u'verify email address'))
def __init__(self, *args, **kwargs):
self.email.label = "New Email Label"
super(RegistrationFormTOS, self).__init__(*args, **kwargs)
def clean_email2(self):
"""
Verifiy that the values entered into the two email fields
match.
"""
if 'email' in self.cleaned_data and 'email2' in self.cleaned_data:
if self.cleaned_data['email'] != self.cleaned_data['email2']:
raise forms.ValidationError(_(u'You must type the same email each time'))
return self.cleaned_data
You access fields in a form via the ‘fields’ dict:
self.fields['email'].label = "New Email Label"
That’s so that you don’t have to worry about form fields having name clashes with the form class methods. (Otherwise you couldn’t have a field named ‘clean’ or ‘is_valid’) Defining the fields directly in the class body is mostly just a convenience.
You should use:
def __init__(self, *args, **kwargs):
super(RegistrationFormTOS, self).__init__(*args, **kwargs)
self.fields['email'].label = "New Email Label"
Note first you should use the super call.
It don’t work for model inheritance, but you can set the label directly in the model
email = models.EmailField("E-Mail Address")
email_confirmation = models.EmailField("Please repeat")
You can set label
as an attribute of field when you define form.
class GiftCardForm(forms.ModelForm):
card_name = forms.CharField(max_length=100, label="Cardholder Name")
card_number = forms.CharField(max_length=50, label="Card Number")
card_code = forms.CharField(max_length=20, label="Security Code")
card_expirate_time = forms.CharField(max_length=100, label="Expiration (MM/YYYY)")
class Meta:
model = models.GiftCard
exclude = ('price', )
Here’s an example taken from Overriding the default fields:
from django.utils.translation import ugettext_lazy as _ class AuthorForm(ModelForm): class Meta: model = Author fields = ('name', 'title', 'birth_date') labels = { 'name': _('Writer'), } help_texts = { 'name': _('Some useful help text.'), } error_messages = { 'name': { 'max_length': _("This writer's name is too long."), }, }
Try on Models.py
email = models.EmailField(verbose_name="E-Mail Address")
email_confirmation = models.EmailField(verbose_name="Please repeat")
if all other solutions don’t work, this one worked for me (to change the user class label to django contrib auth)
#in models.py
User._meta.get_field('username').verbose_name = "new name"
While using a class’ constructor to change the field label for an instance works, it’s better from an object-oriented design standpoint to make the change at the class level if the label doesn’t need to be customized per-instance.
For example, the following will change the label on PasswordChangeForm‘s new_password2 field from "New password confirmation" to "Confirm Password":
class MyPasswordChangeForm(PasswordChangeForm):
PasswordChangeForm.base_fields['new_password2'].label = 'Confirm Password'
Take a look in django/forms/forms.py, you’ll see that DeclarativeFieldsMetaclass removes the fields from a class’ attribute list and places them in base_fields and declared_fields.
class Form(BaseForm, metaclass=DeclarativeFieldsMetaclass):
...
class DeclarativeFieldsMetaclass(MediaDefiningClass):
"""Collect Fields declared on the base classes."""
def __new__(mcs, name, bases, attrs):
# Collect fields from current class and remove them from attrs.
attrs['declared_fields'] = {
key: attrs.pop(key) for key, value in list(attrs.items())
if isinstance(value, Field)
}
new_class = super().__new__(mcs, name, bases, attrs)
# Walk through the MRO.
declared_fields = {}
for base in reversed(new_class.__mro__):
# Collect fields from base class.
if hasattr(base, 'declared_fields'):
declared_fields.update(base.declared_fields)
# Field shadowing.
for attr, value in base.__dict__.items():
if value is None and attr in declared_fields:
declared_fields.pop(attr)
new_class.base_fields = declared_fields
new_class.declared_fields = declared_fields
There’s a comment in BaseForm that provides further explanation:
class BaseForm:
...
# The base_fields class attribute is the *class-wide* definition of
# fields. Because a particular *instance* of the class might want to
# alter self.fields, we create self.fields here by copying base_fields.
# Instances should always modify self.fields; they should not modify
# self.base_fields.