Ticket #10427: django-forms-value.6.diff

File django-forms-value.6.diff, 4.4 KB (added by Ludvig Ericson, 16 years ago)

Added documentation (really)

  • django/forms/forms.py

     
    366366        auto_id = self.auto_id
    367367        if auto_id and 'id' not in attrs and 'id' not in widget.attrs:
    368368            attrs['id'] = auto_id
    369         if not self.form.is_bound:
    370             data = self.form.initial.get(self.name, self.field.initial)
    371             if callable(data):
    372                 data = data()
    373         else:
    374             data = self.data
    375369        if not only_initial:
    376370            name = self.html_name
    377371        else:
    378372            name = self.html_initial_name
    379         return widget.render(name, data, attrs=attrs)
     373        return widget.render(name, self.value, attrs=attrs)
    380374
    381375    def as_text(self, attrs=None, **kwargs):
    382376        """
     
    401395        return self.field.widget.value_from_datadict(self.form.data, self.form.files, self.html_name)
    402396    data = property(_data)
    403397
     398    def _value(self):
     399        """
     400        Returns the value for this BoundField, as rendered in widgets.
     401        """
     402        if not self.form.is_bound:
     403            val = self.form.initial.get(self.name, self.field.initial)
     404            if callable(val):
     405                val = val()
     406        else:
     407            val = self.data
     408        if val is None:
     409            val = ''
     410        return val
     411    value = property(_value)
     412
    404413    def label_tag(self, contents=None, attrs=None):
    405414        """
    406415        Wraps the given contents in a <label>, if the field has an ID attribute.
  • tests/regressiontests/forms/forms.py

     
    11961196<li>Username: <input type="text" name="username" value="stephane" maxlength="10" /></li>
    11971197<li>Password: <input type="password" name="password" /></li>
    11981198
     1199# Bound field values ##########################################################
     1200
     1201It's possible to get to the value which would be used for rendering the widget
     1202for a field by using the BoundField's value attribute.
     1203
     1204>>> class UserRegistration(Form):
     1205...    username = CharField(max_length=10, initial='djangonaut')
     1206...    password = CharField(widget=PasswordInput)
     1207>>> p = UserRegistration({'password': 'foo'})
     1208>>> print 'username.value =', p['username'].value
     1209username.value =
     1210>>> print 'username.data = ', p['username'].data
     1211username.data = None
     1212>>> print 'password.value =', p['password'].value
     1213password.value = foo
     1214>>> print 'password.data =', p['password'].data
     1215password.data = foo
     1216
     1217The value of username is empty because the form is bound -- the value wasn't
     1218specified, and so is empty. This differs if the form were to be unbound:
     1219
     1220>>> p = UserRegistration()
     1221>>> print p['username'].value
     1222djangonaut
     1223
    11991224# Help text ###################################################################
    12001225
    12011226You can specify descriptive text for a field by using the 'help_text' argument
  • docs/ref/forms/fields.txt

     
    293293    <tr><th>Url:</th><td><input type="text" name="url" /></td></tr>
    294294    <tr><th>Comment:</th><td><input type="text" name="comment" /></td></tr>
    295295
     296Field data versus value
     297~~~~~~~~~~~~~~~~~~~~~~~
    296298
     299.. versionadded:: 1.1
     300
     301.. attribute:: Field.value
     302.. attribute:: Field.data
     303
     304Sometimes, it's necessary -- or at least easier -- to render the form entirely
     305on your own. In such a case, you might want to get to what Django's form
     306rendering would use for the HTML `value` attribute.
     307
     308It's quite easy, actually::
     309
     310    >>> f = CommentForm({'comment': 'Foobar'}, initial={'name': 'instance'})
     311    >>> f['name'].value
     312    'instance'
     313    >>> f['comment'].value
     314    'Foobar'
     315
     316The value attribute takes initial data into account on form level (i.e.,
     317passing it to the initializer as seen in previous section), as well as field
     318level.
     319
     320The resolution process is, step by step, the following:
     321
     322 1. If the form has data for this field, use it;
     323 2. if the form has initial data for this field, use it;
     324 3. if the field has initial data, use it; and lastly
     325 4. use the empty string.
     326
    297327Built-in ``Field`` classes
    298328--------------------------
    299329
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