Django 复合小部件
示例
您可以使用创建包含多个小部件的小部件MultiWidget。
from datetime import date
from django.forms.widgets import MultiWidget, Select
from django.utils.dates import MONTHS
class SelectMonthDateWidget(MultiWidget):
"""This widget allows the user to fill in a month and a year.
This represents the first day of this month or, if `last_day=True`, the
last day of this month.
"""
default_nb_years = 10
def __init__(self, attrs=None, years=None, months=None, last_day=False):
self.last_day= last_day
if not years:
this_year = date.today().year
years = range(this_year, this_year + self.default_nb_years)
if not months:
months = MONTHS
# Here we will use two `Select` widgets, one for months and one for years
widgets = (Select(attrs=attrs, choices=months.items()),
Select(attrs=attrs, choices=((y, y) for y in years)))
super().__init__(widgets, attrs)
def format_output(self, rendered_widgets):
"""Concatenates rendered sub-widgets as HTML"""
return (
'<div class="row">'
'<div class="col-xs-6">{}</div>'
'<div class="col-xs-6">{}</div>'
'</div>'
).format(*rendered_widgets)
def decompress(self, value):
"""Split the widget value into subwidgets values.
We expect value to be a valid date formated as `%Y-%m-%d`.
We extract month and year parts from this string.
"""
if value:
value = date(*map(int, value.split('-')))
return [value.month, value.year]
return [None, None]
def value_from_datadict(self, data, files, name):
"""Get the value according to provided `data` (often from `request.POST`)
and `files` (often from `request.FILES`, not used here)
`name` is the name of the form field.
As this is a composite widget, we will grab multiple keys from `data`.
Namely: `field_name_0` (the month) and `field_name_1` (the year).
"""
datalist = [
widget.value_from_datadict(data, files, '{}_{}'.format(name, i))
for i, widget in enumerate(self.widgets)]
try:
# Try to convert it as the first day of a month.
d = date(day=1, month=int(datelist[0]), year=int(datelist[1]))
if self.last_day:
# Transform it to the last day of the month if needed
ifd.month== 12:
d = d.replace(day=31)
else:
d = d.replace(month=d.month+1) - timedelta(days=1)
except (ValueError, TypeError):
# If we failed to recognize a valid date
return ''
else:
# Convert it back to a string with format `%Y-%m-%d`
return str(d)