Ticket #3442: grouped_select.diff

django/newforms/extras/widgets.py

@@ -4 +4 @@
 
 import datetime
 
+import copy
+from itertools import chain
+
 from django.newforms.widgets import Widget, Select
 from django.utils.dates import MONTHS
 from django.utils.safestring import mark_safe
+from django.utils.encoding import StrAndUnicode, force_unicode
+from django.utils.html import escape, conditional_escape
+from django.newforms.util import flatatt
 
-__all__ = ('SelectDateWidget',)
+__all__ = ('SelectDateWidget', 'GroupedSelect')
 
 class SelectDateWidget(Widget):
     """
@@ -59 +65 @@
         if y and m and d:
             return '%s-%s-%s' % (y, m, d)
         return data.get(name, None)
+
+class GroupedSelect(Select):
+    def __init__(self, attrs=None, groups=(), choices=()):
+        super(GroupedSelect, self).__init__(attrs, choices)
+        # groups maps from 'group name' to a list of values in that group
+        # to preserve ordering, it's a list-of-tuples instead of a dict
+        self.groups = groups
+
+    def render(self, name, value, attrs=None, choices=()):
+        if value is None: value = ''
+        final_attrs = self.build_attrs(attrs, name=name)
+        output = [u'<select%s>' % flatatt(final_attrs)]
+        str_value = force_unicode(value) # Normalize to string.
+        allchoices = dict([(force_unicode(k), force_unicode(v))
+            for k, v in chain(self.choices, choices)])
+        for group_label, members in self.groups:
+            group_label = force_unicode(group_label)
+            output.append(u'<optgroup label="%s">' % escape(group_label))
+            for option_value in members:
+                option_value = force_unicode(option_value)
+                try:
+                    option_label = allchoices[option_value]
+                except KeyError:
+                    continue # silently ignore missing elements from the group
+                selected_html = (option_value == str_value) and u' selected="selected"' or ''
+                output.append(u'<option value="%s"%s>%s</option>' % (escape(option_value), selected_html, escape(option_label)))
+            output.append(u'</optgroup>')
+        output.append(u'</select>')
+        return mark_safe(u'\n'.join(output))