Source code for django.forms.boundfield

from __future__ import unicode_literals

import datetime

from django.forms.utils import flatatt, pretty_name
from django.forms.widgets import Textarea, TextInput
from django.utils import six
from django.utils.encoding import (
    force_text, python_2_unicode_compatible, smart_text,
from django.utils.html import conditional_escape, format_html, html_safe
from django.utils.safestring import mark_safe
from django.utils.translation import ugettext_lazy as _

__all__ = ('BoundField',)

UNSET = object()

[docs]class BoundField(object): "A Field plus data" def __init__(self, form, field, name): self.form = form self.field = field = name self.html_name = form.add_prefix(name) self.html_initial_name = form.add_initial_prefix(name) self.html_initial_id = form.add_initial_prefix(self.auto_id) if self.field.label is None: self.label = pretty_name(name) else: self.label = self.field.label self.help_text = field.help_text or '' self._initial_value = UNSET def __str__(self): """Renders this field as an HTML widget.""" if self.field.show_hidden_initial: return self.as_widget() + self.as_hidden(only_initial=True) return self.as_widget() def __iter__(self): """ Yields rendered strings that comprise all widgets in this BoundField. This really is only useful for RadioSelect widgets, so that you can iterate over individual radio buttons in a template. """ id_ = self.field.widget.attrs.get('id') or self.auto_id attrs = {'id': id_} if id_ else {} attrs = self.build_widget_attrs(attrs) for subwidget in self.field.widget.subwidgets(self.html_name, self.value(), attrs): yield subwidget def __len__(self): return len(list(self.__iter__())) def __getitem__(self, idx): # Prevent unnecessary reevaluation when accessing BoundField's attrs # from templates. if not isinstance(idx, six.integer_types + (slice,)): raise TypeError return list(self.__iter__())[idx] @property def errors(self): """ Returns an ErrorList for this field. Returns an empty ErrorList if there are none. """ return self.form.errors.get(, self.form.error_class())
[docs] def as_widget(self, widget=None, attrs=None, only_initial=False): """ Renders the field by rendering the passed widget, adding any HTML attributes passed as attrs. If no widget is specified, then the field's default widget will be used. """ if not widget: widget = self.field.widget if self.field.localize: widget.is_localized = True attrs = attrs or {} attrs = self.build_widget_attrs(attrs, widget) auto_id = self.auto_id if auto_id and 'id' not in attrs and 'id' not in widget.attrs: if not only_initial: attrs['id'] = auto_id else: attrs['id'] = self.html_initial_id if not only_initial: name = self.html_name else: name = self.html_initial_name return force_text(widget.render(name, self.value(), attrs=attrs))
def as_text(self, attrs=None, **kwargs): """ Returns a string of HTML for representing this as an <input type="text">. """ return self.as_widget(TextInput(), attrs, **kwargs) def as_textarea(self, attrs=None, **kwargs): "Returns a string of HTML for representing this as a <textarea>." return self.as_widget(Textarea(), attrs, **kwargs)
[docs] def as_hidden(self, attrs=None, **kwargs): """ Returns a string of HTML for representing this as an <input type="hidden">. """ return self.as_widget(self.field.hidden_widget(), attrs, **kwargs)
@property def data(self): """ Returns the data for this BoundField, or None if it wasn't given. """ return self.field.widget.value_from_datadict(, self.form.files, self.html_name)
[docs] def value(self): """ Returns the value for this BoundField, using the initial value if the form is not bound or the data otherwise. """ if not self.form.is_bound: data = self.initial else: data = self.field.bound_data(, self.form.initial.get(, self.field.initial) ) return self.field.prepare_value(data)
[docs] def label_tag(self, contents=None, attrs=None, label_suffix=None): """ Wraps the given contents in a <label>, if the field has an ID attribute. contents should be 'mark_safe'd to avoid HTML escaping. If contents aren't given, uses the field's HTML-escaped label. If attrs are given, they're used as HTML attributes on the <label> tag. label_suffix allows overriding the form's label_suffix. """ contents = contents or self.label if label_suffix is None: label_suffix = (self.field.label_suffix if self.field.label_suffix is not None else self.form.label_suffix) # Only add the suffix if the label does not end in punctuation. # Translators: If found as last label character, these punctuation # characters will prevent the default label_suffix to be appended to the label if label_suffix and contents and contents[-1] not in _(':?.!'): contents = format_html('{}{}', contents, label_suffix) widget = self.field.widget id_ = widget.attrs.get('id') or self.auto_id if id_: id_for_label = widget.id_for_label(id_) if id_for_label: attrs = dict(attrs or {}, **{'for': id_for_label}) if self.field.required and hasattr(self.form, 'required_css_class'): attrs = attrs or {} if 'class' in attrs: attrs['class'] += ' ' + self.form.required_css_class else: attrs['class'] = self.form.required_css_class attrs = flatatt(attrs) if attrs else '' contents = format_html('<label{}>{}</label>', attrs, contents) else: contents = conditional_escape(contents) return mark_safe(contents)
[docs] def css_classes(self, extra_classes=None): """ Returns a string of space-separated CSS classes for this field. """ if hasattr(extra_classes, 'split'): extra_classes = extra_classes.split() extra_classes = set(extra_classes or []) if self.errors and hasattr(self.form, 'error_css_class'): extra_classes.add(self.form.error_css_class) if self.field.required and hasattr(self.form, 'required_css_class'): extra_classes.add(self.form.required_css_class) return ' '.join(extra_classes)
@property def is_hidden(self): "Returns True if this BoundField's widget is hidden." return self.field.widget.is_hidden @property def auto_id(self): """ Calculates and returns the ID attribute for this BoundField, if the associated Form has specified auto_id. Returns an empty string otherwise. """ auto_id = self.form.auto_id if auto_id and '%s' in smart_text(auto_id): return smart_text(auto_id) % self.html_name elif auto_id: return self.html_name return '' @property def id_for_label(self): """ Wrapper around the field widget's `id_for_label` method. Useful, for example, for focusing on this field regardless of whether it has a single widget or a MultiWidget. """ widget = self.field.widget id_ = widget.attrs.get('id') or self.auto_id return widget.id_for_label(id_) @property def initial(self): data = self.form.initial.get(, self.field.initial) if callable(data): if self._initial_value is not UNSET: data = self._initial_value else: data = data() # If this is an auto-generated default date, nix the # microseconds for standardized handling. See #22502. if (isinstance(data, (datetime.datetime, datetime.time)) and not self.field.widget.supports_microseconds): data = data.replace(microsecond=0) self._initial_value = data return data def build_widget_attrs(self, attrs, widget=None): if not widget: widget = self.field.widget attrs = dict(attrs) # Copy attrs to avoid modifying the argument. if widget.use_required_attribute(self.initial) and self.field.required and self.form.use_required_attribute: attrs['required'] = True if self.field.disabled: attrs['disabled'] = True return attrs
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