Source code for helper
import re
from django.urls import NoReverseMatch, reverse
from django.utils.safestring import mark_safe
from crispy_forms.exceptions import FormHelpersException
from crispy_forms.layout import Layout
from crispy_forms.layout_slice import LayoutSlice
from crispy_forms.utils import TEMPLATE_PACK, flatatt, list_difference, render_field
class DynamicLayoutHandler:
def _check_layout(self):
if self.layout is None:
raise FormHelpersException("You need to set a layout in your FormHelper")
def _check_layout_and_form(self):
self._check_layout()
if self.form is None:
raise FormHelpersException("You need to pass a form instance to your FormHelper")
def all(self):
"""
Returns all layout objects of first level of depth
"""
self._check_layout()
return LayoutSlice(self.layout, slice(0, len(self.layout.fields), 1))
def filter(self, *LayoutClasses, **kwargs):
"""
Returns a LayoutSlice pointing to layout objects of type `LayoutClass`
"""
self._check_layout()
max_level = kwargs.pop("max_level", 0)
greedy = kwargs.pop("greedy", False)
filtered_layout_objects = self.layout.get_layout_objects(LayoutClasses, max_level=max_level, greedy=greedy)
return LayoutSlice(self.layout, filtered_layout_objects)
def filter_by_widget(self, widget_type):
"""
Returns a LayoutSlice pointing to fields with widgets of `widget_type`
"""
self._check_layout_and_form()
layout_field_names = self.layout.get_field_names()
# Let's filter all fields with widgets like widget_type
filtered_fields = []
for pointer in layout_field_names:
if isinstance(self.form.fields[pointer[1]].widget, widget_type):
filtered_fields.append(pointer)
return LayoutSlice(self.layout, filtered_fields)
def exclude_by_widget(self, widget_type):
"""
Returns a LayoutSlice pointing to fields with widgets NOT matching `widget_type`
"""
self._check_layout_and_form()
layout_field_names = self.layout.get_field_names()
# Let's exclude all fields with widgets like widget_type
filtered_fields = []
for pointer in layout_field_names:
if not isinstance(self.form.fields[pointer[1]].widget, widget_type):
filtered_fields.append(pointer)
return LayoutSlice(self.layout, filtered_fields)
def __getitem__(self, key):
"""
Return a LayoutSlice that makes changes affect the current instance of the layout
and not a copy.
"""
# when key is a string containing the field name
if isinstance(key, str):
# Django templates access FormHelper attributes using dictionary [] operator
# This could be a helper['form_id'] access, not looking for a field
if hasattr(self, key):
return getattr(self, key)
self._check_layout()
layout_field_names = self.layout.get_field_names()
filtered_field = []
for pointer in layout_field_names:
# There can be an empty pointer
if len(pointer) == 2 and pointer[1] == key:
filtered_field.append(pointer)
return LayoutSlice(self.layout, filtered_field)
return LayoutSlice(self.layout, key)
def __setitem__(self, key, value):
self.layout[key] = value
def __delitem__(self, key):
del self.layout.fields[key]
def __len__(self):
if self.layout is not None:
return len(self.layout.fields)
else:
return 0
[docs]class FormHelper(DynamicLayoutHandler):
"""
This class controls the form rendering behavior of the form passed to
the `{% crispy %}` tag. For doing so you will need to set its attributes
and pass the corresponding helper object to the tag::
{% crispy form form.helper %}
Let's see what attributes you can set and what form behaviors they apply to:
**form_method**: Specifies form method attribute.
You can set it to 'POST' or 'GET'. Defaults to 'POST'
**form_action**: Applied to the form action attribute:
- Can be a named url in your URLconf that can be executed via the `{% url %}` template tag. \
Example: 'show_my_profile'. In your URLconf you could have something like::
url(r'^show/profile/$', 'show_my_profile_view', name = 'show_my_profile')
- It can simply point to a URL '/whatever/blabla/'.
**form_id**: Generates a form id for dom identification.
If no id provided then no id attribute is created on the form.
**form_class**: String containing separated CSS classes to be applied
to form class attribute. The form will always have by default
'uniForm' class.
**form_group_wrapper_class**: String containing separated CSS classes to be applied
to each row of inputs.
**form_tag**: It specifies if <form></form> tags should be rendered when using a Layout.
If set to False it renders the form without the <form></form> tags. Defaults to True.
**form_error_title**: If a form has `non_field_errors` to display, they
are rendered in a div. You can set title's div with this attribute.
Example: "Oooops!" or "Form Errors"
**formset_error_title**: If a formset has `non_form_errors` to display, they
are rendered in a div. You can set title's div with this attribute.
**form_style**: Uni-form has two built in different form styles. You can choose
your favorite. This can be set to "default" or "inline". Defaults to "default".
**include_media**: Whether to automatically include form media. Set to False if
you want to manually include form media outside the form. Defaults to True.
Public Methods:
**add_input(input)**: You can add input buttons using this method. Inputs
added using this method will be rendered at the end of the form/formset.
**add_layout(layout)**: You can add a `Layout` object to `FormHelper`. The Layout
specifies in a simple, clean and DRY way how the form fields should be rendered.
You can wrap fields, order them, customize pretty much anything in the form.
Best way to add a helper to a form is adding a property named helper to the form
that returns customized `FormHelper` object::
from crispy_forms.helper import FormHelper
from crispy_forms.layout import Submit
class MyForm(forms.Form):
title = forms.CharField(_("Title"))
@property
def helper(self):
helper = FormHelper()
helper.form_id = 'this-form-rocks'
helper.form_class = 'search'
helper.add_input(Submit('save', 'save'))
[...]
return helper
You can use it in a template doing::
{% load crispy_forms_tags %}
{% crispy form %}
"""
_form_method = "post"
_form_action = ""
_form_style = "default"
form = None
form_id = ""
form_class = ""
form_group_wrapper_class = ""
layout = None
form_tag = True
form_error_title = None
formset_error_title = None
form_show_errors = True
render_unmentioned_fields = False
render_hidden_fields = False
render_required_fields = False
_help_text_inline = False
_error_text_inline = True
html5_required = False
form_show_labels = True
template = None
field_template = None
disable_csrf = False
use_custom_control = True
label_class = ""
field_class = ""
include_media = True
def __init__(self, form=None):
self.attrs = {}
self.inputs = []
if form is not None:
self.form = form
self.layout = self.build_default_layout(form)
def build_default_layout(self, form):
return Layout(*form.fields.keys())
@property
def form_method(self):
return self._form_method
@form_method.setter
def form_method(self, method):
if method.lower() not in ("get", "post"):
raise FormHelpersException(
"Only GET and POST are valid in the \
form_method helper attribute"
)
self._form_method = method.lower()
@property
def form_action(self):
try:
return reverse(self._form_action)
except NoReverseMatch:
return self._form_action
@form_action.setter
def form_action(self, action):
self._form_action = action
@property
def form_style(self):
if self._form_style == "default":
return ""
if self._form_style == "inline":
return "inlineLabels"
@form_style.setter
def form_style(self, style):
if style.lower() not in ("default", "inline"):
raise FormHelpersException(
"Only default and inline are valid in the \
form_style helper attribute"
)
self._form_style = style.lower()
@property
def help_text_inline(self):
return self._help_text_inline
@help_text_inline.setter
def help_text_inline(self, flag):
self._help_text_inline = flag
self._error_text_inline = not flag
@property
def error_text_inline(self):
return self._error_text_inline
@error_text_inline.setter
def error_text_inline(self, flag):
self._error_text_inline = flag
self._help_text_inline = not flag
def add_input(self, input_object):
self.inputs.append(input_object)
def add_layout(self, layout):
self.layout = layout
[docs] def render_layout(self, form, context, template_pack=TEMPLATE_PACK):
"""
Returns safe html of the rendering of the layout
"""
form.rendered_fields = set()
form.crispy_field_template = self.field_template
# This renders the specified Layout strictly
html = self.layout.render(form, self.form_style, context, template_pack=template_pack)
# Rendering some extra fields if specified
if self.render_unmentioned_fields or self.render_hidden_fields or self.render_required_fields:
fields = tuple(form.fields.keys())
left_fields_to_render = list_difference(fields, form.rendered_fields)
for field in left_fields_to_render:
if (
self.render_unmentioned_fields
or (self.render_hidden_fields and form.fields[field].widget.is_hidden)
or (self.render_required_fields and form.fields[field].widget.is_required)
):
html += render_field(field, form, self.form_style, context, template_pack=template_pack)
return mark_safe(html)
[docs] def get_attributes(self, template_pack=TEMPLATE_PACK): # noqa: C901
"""
Used by crispy_forms_tags to get helper attributes
"""
items = {
"disable_csrf": self.disable_csrf,
"error_text_inline": self.error_text_inline,
"field_class": self.field_class,
"field_template": self.field_template or "%s/field.html" % template_pack,
"form_method": self.form_method.strip(),
"form_show_errors": self.form_show_errors,
"form_show_labels": self.form_show_labels,
"form_style": self.form_style.strip(),
"form_tag": self.form_tag,
"help_text_inline": self.help_text_inline,
"html5_required": self.html5_required,
"include_media": self.include_media,
"label_class": self.label_class,
"use_custom_control": self.use_custom_control,
}
if template_pack == "bootstrap4":
if "form-horizontal" in self.form_class.split():
bootstrap_size_match = re.findall(r"col(-(xl|lg|md|sm))?-(\d+)", self.label_class)
if bootstrap_size_match:
offset_pattern = "offset%s-%s"
items["bootstrap_checkbox_offsets"] = [
offset_pattern % (m[0], m[-1]) for m in bootstrap_size_match
]
else:
bootstrap_size_match = re.findall(r"col-(lg|md|sm|xs)-(\d+)", self.label_class)
if bootstrap_size_match:
offset_pattern = "col-%s-offset-%s"
items["bootstrap_checkbox_offsets"] = [offset_pattern % m for m in bootstrap_size_match]
items["attrs"] = {}
if self.attrs:
items["attrs"] = self.attrs.copy()
if self.form_action:
items["attrs"]["action"] = self.form_action.strip()
if self.form_id:
items["attrs"]["id"] = self.form_id.strip()
if self.form_class:
# uni_form TEMPLATE PACK has a uniForm class by default
if template_pack == "uni_form":
items["attrs"]["class"] = "uniForm %s" % self.form_class.strip()
else:
items["attrs"]["class"] = self.form_class.strip()
else:
if template_pack == "uni_form":
items["attrs"]["class"] = self.attrs.get("class", "") + " uniForm"
if self.form_group_wrapper_class:
items["attrs"]["form_group_wrapper_class"] = self.form_group_wrapper_class
items["flat_attrs"] = flatatt(items["attrs"])
if self.inputs:
items["inputs"] = self.inputs
if self.form_error_title:
items["form_error_title"] = self.form_error_title.strip()
if self.formset_error_title:
items["formset_error_title"] = self.formset_error_title.strip()
for attribute_name, value in self.__dict__.items():
if (
attribute_name not in items
and attribute_name not in ["layout", "inputs"]
and not attribute_name.startswith("_")
):
items[attribute_name] = value
return items