如何通过相关模型对CheckboxSelectMultiple
生成的复选框进行分组?
最好通过示例来证明这一点。
models.py:
class FeatureCategory(models.Model):
name = models.CharField(max_length=30)
class Feature(models.Model):
name = models.CharField(max_length=30)
category = models.ForeignKey(FeatureCategory)
class Widget(models.Model):
name = models.CharField(max_length=30)
features = models.ManyToManyField(Feature, blank=True)
forms.py:
class WidgetForm(forms.ModelForm):
features = forms.ModelMultipleChoiceField(
queryset=Feature.objects.all(),
widget=forms.CheckboxSelectMultiple,
required=False
)
class Meta:
model = Widget
views.py:
def edit_widget(request):
form = WidgetForm()
return render(request, 'template.html', {'form': form})
template.html:
{{ form.as_p }}
以上产生以下输出:
[] Widget 1
[] Widget 2
[] Widget 3
[] Widget 1
[] Widget 2
我希望功能复选框按功能类别分组(基于ForeignKey
):
Category 1:
[] Widget 1
[] Widget 2
[] Widget 3
Category 2:
[] Widget 1
[] Widget 2
我怎样才能做到这一点?我尝试使用{% regroup %}
模板标记无效。
任何建议都非常感谢。
感谢。
答案 0 :(得分:14)
您必须编写自定义CheckboxSelectMultiple
窗口小部件。使用snippet我尝试通过在字段CheckboxSelectMultiple
中添加category_name
作为属性来使attrs
字段可迭代。这样我以后就可以在模板中使用regroup
标记了。
以下代码是根据您的需要从代码段修改的,显然这段代码可以更清晰,更通用,但此时它不是通用的。
forms.py
from django import forms
from django.forms import Widget
from django.forms.widgets import SubWidget
from django.forms.util import flatatt
from django.utils.html import conditional_escape
from django.utils.encoding import StrAndUnicode, force_unicode
from django.utils.safestring import mark_safe
from itertools import chain
import ast
from mysite.models import Widget as wid # your model name is conflicted with django.forms.Widget
from mysite.models import Feature
class CheckboxInput(SubWidget):
"""
An object used by CheckboxRenderer that represents a single
<input type='checkbox'>.
"""
def __init__(self, name, value, attrs, choice, index):
self.name, self.value = name, value
self.attrs = attrs
self.choice_value = force_unicode(choice[1])
self.choice_label = force_unicode(choice[2])
self.attrs.update({'cat_name': choice[0]})
self.index = index
def __unicode__(self):
return self.render()
def render(self, name=None, value=None, attrs=None, choices=()):
name = name or self.name
value = value or self.value
attrs = attrs or self.attrs
if 'id' in self.attrs:
label_for = ' for="%s_%s"' % (self.attrs['id'], self.index)
else:
label_for = ''
choice_label = conditional_escape(force_unicode(self.choice_label))
return mark_safe(u'<label%s>%s %s</label>' % (label_for, self.tag(), choice_label))
def is_checked(self):
return self.choice_value in self.value
def tag(self):
if 'id' in self.attrs:
self.attrs['id'] = '%s_%s' % (self.attrs['id'], self.index)
final_attrs = dict(self.attrs, type='checkbox', name=self.name, value=self.choice_value)
if self.is_checked():
final_attrs['checked'] = 'checked'
return mark_safe(u'<input%s />' % flatatt(final_attrs))
class CheckboxRenderer(StrAndUnicode):
def __init__(self, name, value, attrs, choices):
self.name, self.value, self.attrs = name, value, attrs
self.choices = choices
def __iter__(self):
for i, choice in enumerate(self.choices):
yield CheckboxInput(self.name, self.value, self.attrs.copy(), choice, i)
def __getitem__(self, idx):
choice = self.choices[idx] # Let the IndexError propogate
return CheckboxInput(self.name, self.value, self.attrs.copy(), choice, idx)
def __unicode__(self):
return self.render()
def render(self):
"""Outputs a <ul> for this set of checkbox fields."""
return mark_safe(u'<ul>\n%s\n</ul>' % u'\n'.join([u'<li>%s</li>'
% force_unicode(w) for w in self]))
class CheckboxSelectMultipleIter(forms.CheckboxSelectMultiple):
"""
Checkbox multi select field that enables iteration of each checkbox
Similar to django.forms.widgets.RadioSelect
"""
renderer = CheckboxRenderer
def __init__(self, *args, **kwargs):
# Override the default renderer if we were passed one.
renderer = kwargs.pop('renderer', None)
if renderer:
self.renderer = renderer
super(CheckboxSelectMultipleIter, self).__init__(*args, **kwargs)
def subwidgets(self, name, value, attrs=None, choices=()):
for widget in self.get_renderer(name, value, attrs, choices):
yield widget
def get_renderer(self, name, value, attrs=None, choices=()):
"""Returns an instance of the renderer."""
choices_ = [ast.literal_eval(i[1]).iteritems() for i in self.choices]
choices_ = [(a[1], b[1], c[1]) for a, b, c in choices_]
if value is None: value = ''
str_values = set([force_unicode(v) for v in value]) # Normalize to string.
if attrs is None:
attrs = {}
if 'id' not in attrs:
attrs['id'] = name
final_attrs = self.build_attrs(attrs)
choices = list(chain(choices_, choices))
return self.renderer(name, str_values, final_attrs, choices)
def render(self, name, value, attrs=None, choices=()):
return self.get_renderer(name, value, attrs, choices).render()
def id_for_label(self, id_):
if id_:
id_ += '_0'
return id_
class WidgetForm(forms.ModelForm):
features = forms.ModelMultipleChoiceField(
queryset=Feature.objects.all().values('id', 'name', 'category__name'),
widget=CheckboxSelectMultipleIter,
required=False
)
class Meta:
model = wid
然后在模板中:
{% for field in form %}
{% if field.name == 'features' %}
{% regroup field by attrs.cat_name as list %}
<ul>
{% for el in list %}
<li>{{el.grouper}}
<ul>
{% for e in el.list %}
{{e}} <br />
{% endfor %}
</ul>
</li>
{% endfor %}
</ul>
{% else %}
{{field.label}}: {{field}}
{% endif %}
{% endfor %}
结果的: 我在类别表中添加了国家/地区名称,并在功能表中添加了城市名称,因此在模板中我可以根据国家/地区(类别)重新组合城市(功能)
答案 1 :(得分:0)
这是当前版本的Django(〜2.1)的解决方案。
## forms.py
from itertools import groupby
from django import forms
from django.forms.models import ModelChoiceIterator, ModelMultipleChoiceField
from .models import Feature, Widget
class GroupedModelMultipleChoiceField(ModelMultipleChoiceField):
def __init__(self, group_by_field, group_label=None, *args, **kwargs):
"""
``group_by_field`` is the name of a field on the model
``group_label`` is a function to return a label for each choice group
"""
super(GroupedModelMultipleChoiceField, self).__init__(*args, **kwargs)
self.group_by_field = group_by_field
if group_label is None:
self.group_label = lambda group: group
else:
self.group_label = group_label
def _get_choices(self):
if hasattr(self, '_choices'):
return self._choices
return GroupedModelChoiceIterator(self)
choices = property(_get_choices, ModelMultipleChoiceField._set_choices)
class GroupedModelChoiceIterator(ModelChoiceIterator):
def __iter__(self):
"""Now yields grouped choices."""
if self.field.empty_label is not None:
yield ("", self.field.empty_label)
for group, choices in groupby(
self.queryset.all(),
lambda row: getattr(row, self.field.group_by_field)):
if group is None:
for ch in choices:
yield self.choice(ch)
else:
yield (
self.field.group_label(group),
[self.choice(ch) for ch in choices])
class WidgetForm(forms.ModelForm):
class Meta:
model = Widget
fields = ['features',]
def __init__(self, *args, **kwargs):
super(WidgetForm, self).__init__(*args, **kwargs)
self.fields['features'] = GroupedModelMultipleChoiceField(
group_by_field='category',
queryset=Feature.objects.all(),
widget=forms.CheckboxSelectMultiple(),
required=False)
然后,您可以在模板中使用{{ form.as_p }}
进行正确分组的选择。
如果您想使用regroup
模板标记并遍历所有选择,则还需要引用以下自定义小部件:
class GroupedCheckboxSelectMultiple(forms.CheckboxSelectMultiple):
def optgroups(self, name, value, attrs=None):
"""
The group name is passed as an argument to the ``create_option`` method (below).
"""
groups = []
has_selected = False
for index, (option_value, option_label) in enumerate(self.choices):
if option_value is None:
option_value = ''
subgroup = []
if isinstance(option_label, (list, tuple)):
group_name = option_value
subindex = 0
choices = option_label
else:
group_name = None
subindex = None
choices = [(option_value, option_label)]
groups.append((group_name, subgroup, index))
for subvalue, sublabel in choices:
selected = (
str(subvalue) in value and
(not has_selected or self.allow_multiple_selected)
)
has_selected |= selected
subgroup.append(self.create_option(
name, subvalue, sublabel, selected, index,
subindex=subindex, attrs=attrs, group=group_name,
))
if subindex is not None:
subindex += 1
return groups
def create_option(self, name, value, label, selected, index, subindex=None, attrs=None, group=None):
"""
Added a ``group`` argument which is included in the returned dictionary.
"""
index = str(index) if subindex is None else "%s_%s" % (index, subindex)
if attrs is None:
attrs = {}
option_attrs = self.build_attrs(self.attrs, attrs) if self.option_inherits_attrs else {}
if selected:
option_attrs.update(self.checked_attribute)
if 'id' in option_attrs:
option_attrs['id'] = self.id_for_label(option_attrs['id'], index)
return {
'name': name,
'value': value,
'label': label,
'selected': selected,
'index': index,
'attrs': option_attrs,
'type': self.input_type,
'template_name': self.option_template_name,
'wrap_label': True,
'group': group,
}
class WidgetForm(forms.ModelForm):
class Meta:
model = Widget
fields = ['features',]
def __init__(self, *args, **kwargs):
super(WidgetForm, self).__init__(*args, **kwargs)
self.fields['features'] = GroupedModelMultipleChoiceField(
group_by_field='category',
queryset=Feature.objects.all(),
widget=GroupedCheckboxSelectMultiple(),
required=False)
然后,以下内容应在您的模板中起作用:
{% regroup form.features by data.group as feature_list %}
{% for group in feature_list %}
<h6>{{ group.grouper|default:"Other Features" }}</h6>
<ul>
{% for choice in group.list %}
<li>{{ choice }}</li>
{% endfor %}
</ul>
</div>
{% endfor %}
贷记到以下页面以了解部分解决方案: