A widget is Django’s representation of an HTML input element. The widget handles the rendering of the HTML, and the extraction of data from a GET/POST dictionary that corresponds to the widget.
The HTML generated by the built-in widgets uses HTML5 syntax, targeting
<!DOCTYPE html>
. For example, it uses boolean attributes such as checked
rather than the XHTML style of checked='checked'
.
Tip
Widgets should not be confused with the form fields. Form fields deal with the logic of input validation and are used directly in templates. Widgets deal with rendering of HTML form input elements on the web page and extraction of raw submitted data. However, widgets do need to be assigned to form fields.
Whenever you specify a field on a form, Django will use a default widget that is appropriate to the type of data that is to be displayed. To find which widget is used on which field, see the documentation about Built-in Field classes.
However, if you want to use a different widget for a field, you can
use the widget
argument on the field definition. For example:
from django import forms
class CommentForm(forms.Form):
name = forms.CharField()
url = forms.URLField()
comment = forms.CharField(widget=forms.Textarea)
This would specify a form with a comment that uses a larger Textarea
widget, rather than the default TextInput
widget.
Many widgets have optional extra arguments; they can be set when defining the
widget on the field. In the following example, the
years
attribute is set for a
SelectDateWidget
:
from django import forms
BIRTH_YEAR_CHOICES = ["1980", "1981", "1982"]
FAVORITE_COLORS_CHOICES = [
("blue", "Blue"),
("green", "Green"),
("black", "Black"),
]
class SimpleForm(forms.Form):
birth_year = forms.DateField(
widget=forms.SelectDateWidget(years=BIRTH_YEAR_CHOICES)
)
favorite_colors = forms.MultipleChoiceField(
required=False,
widget=forms.CheckboxSelectMultiple,
choices=FAVORITE_COLORS_CHOICES,
)
See the Built-in widgets for more information about which widgets are available and which arguments they accept.
Select
widget¶Widgets inheriting from the Select
widget deal with choices. They
present the user with a list of options to choose from. The different widgets
present this choice differently; the Select
widget itself uses a
<select>
HTML list representation, while RadioSelect
uses radio
buttons.
Select
widgets are used by default on ChoiceField
fields. The
choices displayed on the widget are inherited from the ChoiceField
and
changing ChoiceField.choices
will update Select.choices
. For
example:
>>> from django import forms
>>> CHOICES = [("1", "First"), ("2", "Second")]
>>> choice_field = forms.ChoiceField(widget=forms.RadioSelect, choices=CHOICES)
>>> choice_field.choices
[('1', 'First'), ('2', 'Second')]
>>> choice_field.widget.choices
[('1', 'First'), ('2', 'Second')]
>>> choice_field.widget.choices = []
>>> choice_field.choices = [("1", "First and only")]
>>> choice_field.widget.choices
[('1', 'First and only')]
Widgets which offer a choices
attribute can however be used
with fields which are not based on choice – such as a CharField
–
but it is recommended to use a ChoiceField
-based field when the
choices are inherent to the model and not just the representational widget.
When Django renders a widget as HTML, it only renders very minimal markup -
Django doesn’t add class names, or any other widget-specific attributes. This
means, for example, that all TextInput
widgets will appear the same
on your web pages.
There are two ways to customize widgets: per widget instance and per widget class.
If you want to make one widget instance look different from another, you will need to specify additional attributes at the time when the widget object is instantiated and assigned to a form field (and perhaps add some rules to your CSS files).
For example, take the following form:
from django import forms
class CommentForm(forms.Form):
name = forms.CharField()
url = forms.URLField()
comment = forms.CharField()
This form will include three default TextInput
widgets, with default
rendering – no CSS class, no extra attributes. This means that the input boxes
provided for each widget will be rendered exactly the same:
>>> f = CommentForm(auto_id=False)
>>> f.as_table()
<tr><th>Name:</th><td><input type="text" name="name" required></td></tr>
<tr><th>Url:</th><td><input type="url" name="url" required></td></tr>
<tr><th>Comment:</th><td><input type="text" name="comment" required></td></tr>
On a real web page, you probably don’t want every widget to look the same. You
might want a larger input element for the comment, and you might want the
‘name’ widget to have some special CSS class. It is also possible to specify
the ‘type’ attribute to take advantage of the new HTML5 input types. To do
this, you use the Widget.attrs
argument when creating the widget:
class CommentForm(forms.Form):
name = forms.CharField(widget=forms.TextInput(attrs={"class": "special"}))
url = forms.URLField()
comment = forms.CharField(widget=forms.TextInput(attrs={"size": "40"}))
You can also modify a widget in the form definition:
class CommentForm(forms.Form):
name = forms.CharField()
url = forms.URLField()
comment = forms.CharField()
name.widget.attrs.update({"class": "special"})
comment.widget.attrs.update(size="40")
Or if the field isn’t declared directly on the form (such as model form fields),
you can use the Form.fields
attribute:
class CommentForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.fields["name"].widget.attrs.update({"class": "special"})
self.fields["comment"].widget.attrs.update(size="40")
Django will then include the extra attributes in the rendered output:
>>> f = CommentForm(auto_id=False)
>>> f.as_table()
<tr><th>Name:</th><td><input type="text" name="name" class="special" required></td></tr>
<tr><th>Url:</th><td><input type="url" name="url" required></td></tr>
<tr><th>Comment:</th><td><input type="text" name="comment" size="40" required></td></tr>
You can also set the HTML id
using attrs
. See
BoundField.id_for_label
for an example.
With widgets, it is possible to add assets (css
and javascript
)
and more deeply customize their appearance and behavior.
In a nutshell, you will need to subclass the widget and either define a “Media” inner class or create a “media” property.
These methods involve somewhat advanced Python programming and are described in detail in the Form Assets topic guide.
Base widget classes Widget
and MultiWidget
are subclassed by
all the built-in widgets and may serve as a
foundation for custom widgets.
Widget
¶This abstract class cannot be rendered, but provides the basic attribute
attrs
. You may also implement or override the
render()
method on custom widgets.
A dictionary containing HTML attributes to be set on the rendered widget.
>>> from django import forms
>>> name = forms.TextInput(attrs={"size": 10, "title": "Your name"})
>>> name.render("name", "A name")
'<input title="Your name" type="text" name="name" value="A name" size="10">'
If you assign a value of True
or False
to an attribute,
it will be rendered as an HTML5 boolean attribute:
>>> name = forms.TextInput(attrs={"required": True})
>>> name.render("name", "A name")
'<input name="name" type="text" value="A name" required>'
>>>
>>> name = forms.TextInput(attrs={"required": False})
>>> name.render("name", "A name")
'<input name="name" type="text" value="A name">'
An attribute that defaults to True
. If set to False
, the
microseconds part of datetime
and
time
values will be set to 0
.
Cleans and returns a value for use in the widget template. value
isn’t guaranteed to be valid input, therefore subclass implementations
should program defensively.
Returns a dictionary of values to use when rendering the widget
template. By default, the dictionary contains a single key,
'widget'
, which is a dictionary representation of the widget
containing the following keys:
'name'
: The name of the field from the name
argument.
'is_hidden'
: A boolean indicating whether or not this widget is
hidden.
'required'
: A boolean indicating whether or not the field for
this widget is required.
'value'
: The value as returned by format_value()
.
'attrs'
: HTML attributes to be set on the rendered widget. The
combination of the attrs
attribute and the attrs
argument.
'template_name'
: The value of self.template_name
.
Widget
subclasses can provide custom context values by overriding
this method.
Returns the HTML ID attribute of this widget for use by a <label>
,
given the ID of the field. Returns an empty string if an ID isn’t
available.
This hook is necessary because some widgets have multiple HTML elements and, thus, multiple IDs. In that case, this method should return an ID value that corresponds to the first ID in the widget’s tags.
Renders a widget to HTML using the given renderer. If renderer
is
None
, the renderer from the FORM_RENDERER
setting is
used.
Given a dictionary of data and this widget’s name, returns the value
of this widget. files
may contain data coming from
request.FILES
. Returns None
if a value wasn’t provided. Note also that value_from_datadict
may
be called more than once during handling of form data, so if you
customize it and add expensive processing, you should implement some
caching mechanism yourself.
Given data
and files
dictionaries and this widget’s name,
returns whether or not there’s data or files for the widget.
The method’s result affects whether or not a field in a model form falls back to its default.
Special cases are CheckboxInput
,
CheckboxSelectMultiple
, and
SelectMultiple
, which always return
False
because an unchecked checkbox and unselected
<select multiple>
don’t appear in the data of an HTML form
submission, so it’s unknown whether or not the user submitted a value.
An attribute to identify if the widget should be grouped in a
<fieldset>
with a <legend>
when rendered. Defaults to False
but is True
when the widget contains multiple <input>
tags such as
CheckboxSelectMultiple
,
RadioSelect
,
MultiWidget
,
SplitDateTimeWidget
, and
SelectDateWidget
.
Given a form field’s initial
value, returns whether or not the
widget can be rendered with the required
HTML attribute. Forms use
this method along with Field.required
and Form.use_required_attribute
to determine whether or not
to display the required
attribute for each field.
By default, returns False
for hidden widgets and True
otherwise. Special cases are FileInput
and
ClearableFileInput
, which return False
when
initial
is set, and CheckboxSelectMultiple
,
which always returns False
because browser validation would require
all checkboxes to be checked instead of at least one.
Override this method in custom widgets that aren’t compatible with
browser validation. For example, a WSYSIWG text editor widget backed by
a hidden textarea
element may want to always return False
to
avoid browser validation on the hidden field.
MultiWidget
¶A widget that is composed of multiple widgets.
MultiWidget
works hand in hand with the
MultiValueField
.
MultiWidget
has one required argument:
An iterable containing the widgets needed. For example:
>>> from django.forms import MultiWidget, TextInput
>>> widget = MultiWidget(widgets=[TextInput, TextInput])
>>> widget.render("name", ["john", "paul"])
'<input type="text" name="name_0" value="john"><input type="text" name="name_1" value="paul">'
You may provide a dictionary in order to specify custom suffixes for
the name
attribute on each subwidget. In this case, for each
(key, widget)
pair, the key will be appended to the name
of the
widget in order to generate the attribute value. You may provide the
empty string (''
) for a single key, in order to suppress the suffix
for one widget. For example:
>>> widget = MultiWidget(widgets={"": TextInput, "last": TextInput})
>>> widget.render("name", ["john", "paul"])
'<input type="text" name="name" value="john"><input type="text" name="name_last" value="paul">'
And one required method:
This method takes a single “compressed” value from the field and returns a list of “decompressed” values. The input value can be assumed valid, but not necessarily non-empty.
This method must be implemented by the subclass, and since the value may be empty, the implementation must be defensive.
The rationale behind “decompression” is that it is necessary to “split” the combined value of the form field into the values for each widget.
An example of this is how SplitDateTimeWidget
turns a
datetime
value into a list with date and time split
into two separate values:
from django.forms import MultiWidget
class SplitDateTimeWidget(MultiWidget):
# ...
def decompress(self, value):
if value:
return [value.date(), value.time()]
return [None, None]
Tip
Note that MultiValueField
has a
complementary method compress()
with the opposite responsibility - to combine cleaned values of
all member fields into one.
It provides some custom context:
In addition to the 'widget'
key described in
Widget.get_context()
, MultiWidget
adds a
widget['subwidgets']
key.
These can be looped over in the widget template:
{% for subwidget in widget.subwidgets %}
{% include subwidget.template_name with widget=subwidget %}
{% endfor %}
Here’s an example widget which subclasses MultiWidget
to display
a date with the day, month, and year in different select boxes. This widget
is intended to be used with a DateField
rather than
a MultiValueField
, thus we have implemented
value_from_datadict()
:
from datetime import date
from django import forms
class DateSelectorWidget(forms.MultiWidget):
def __init__(self, attrs=None):
days = [(day, day) for day in range(1, 32)]
months = [(month, month) for month in range(1, 13)]
years = [(year, year) for year in [2018, 2019, 2020]]
widgets = [
forms.Select(attrs=attrs, choices=days),
forms.Select(attrs=attrs, choices=months),
forms.Select(attrs=attrs, choices=years),
]
super().__init__(widgets, attrs)
def decompress(self, value):
if isinstance(value, date):
return [value.day, value.month, value.year]
elif isinstance(value, str):
year, month, day = value.split("-")
return [day, month, year]
return [None, None, None]
def value_from_datadict(self, data, files, name):
day, month, year = super().value_from_datadict(data, files, name)
# DateField expects a single string that it can parse into a date.
return "{}-{}-{}".format(year, month, day)
The constructor creates several Select
widgets in a list. The
super()
method uses this list to set up the widget.
The required method decompress()
breaks up a
datetime.date
value into the day, month, and year values corresponding
to each widget. If an invalid date was selected, such as the non-existent
30th February, the DateField
passes this method a
string instead, so that needs parsing. The final return
handles when
value
is None
, meaning we don’t have any defaults for our
subwidgets.
The default implementation of value_from_datadict()
returns a
list of values corresponding to each Widget
. This is appropriate when
using a MultiWidget
with a MultiValueField
. But
since we want to use this widget with a DateField
,
which takes a single value, we have overridden this method. The
implementation here combines the data from the subwidgets into a string in
the format that DateField
expects.
Django provides a representation of all the basic HTML widgets, plus some
commonly used groups of widgets in the django.forms.widgets
module,
including the input of text, various checkboxes
and selectors, uploading files,
and handling of multi-valued input.
These widgets make use of the HTML elements input
and textarea
.
TextInput
¶input_type
: 'text'
template_name
: 'django/forms/widgets/text.html'
Renders as: <input type="text" ...>
NumberInput
¶input_type
: 'number'
template_name
: 'django/forms/widgets/number.html'
Renders as: <input type="number" ...>
Beware that not all browsers support entering localized numbers in
number
input types. Django itself avoids using them for fields having
their localize
property set to True
.
EmailInput
¶input_type
: 'email'
template_name
: 'django/forms/widgets/email.html'
Renders as: <input type="email" ...>
URLInput
¶input_type
: 'url'
template_name
: 'django/forms/widgets/url.html'
Renders as: <input type="url" ...>
PasswordInput
¶input_type
: 'password'
template_name
: 'django/forms/widgets/password.html'
Renders as: <input type="password" ...>
Takes one optional argument:
Determines whether the widget will have a value filled in when the
form is re-displayed after a validation error (default is False
).
DateInput
¶input_type
: 'text'
template_name
: 'django/forms/widgets/date.html'
Renders as: <input type="text" ...>
Takes same arguments as TextInput
, with one more optional argument:
The format in which this field’s initial value will be displayed.
If no format
argument is provided, the default format is the first
format found in DATE_INPUT_FORMATS
and respects
Format localization.
DateTimeInput
¶input_type
: 'text'
template_name
: 'django/forms/widgets/datetime.html'
Renders as: <input type="text" ...>
Takes same arguments as TextInput
, with one more optional argument:
The format in which this field’s initial value will be displayed.
If no format
argument is provided, the default format is the first
format found in DATETIME_INPUT_FORMATS
and respects
Format localization.
By default, the microseconds part of the time value is always set to 0
.
If microseconds are required, use a subclass with the
supports_microseconds
attribute set to True
.
TimeInput
¶input_type
: 'text'
template_name
: 'django/forms/widgets/time.html'
Renders as: <input type="text" ...>
Takes same arguments as TextInput
, with one more optional argument:
The format in which this field’s initial value will be displayed.
If no format
argument is provided, the default format is the first
format found in TIME_INPUT_FORMATS
and respects
Format localization.
For the treatment of microseconds, see DateTimeInput
.
Textarea
¶template_name
: 'django/forms/widgets/textarea.html'
Renders as: <textarea>...</textarea>
These widgets make use of the HTML elements <select>
,
<input type="checkbox">
, and <input type="radio">
.
Widgets that render multiple choices have an option_template_name
attribute
that specifies the template used to render each choice. For example, for the
Select
widget, select_option.html
renders the <option>
for a
<select>
.
CheckboxInput
¶Select
¶template_name
: 'django/forms/widgets/select.html'
option_template_name
: 'django/forms/widgets/select_option.html'
Renders as: <select><option ...>...</select>
NullBooleanSelect
¶template_name
: 'django/forms/widgets/select.html'
option_template_name
: 'django/forms/widgets/select_option.html'
Select widget with options ‘Unknown’, ‘Yes’ and ‘No’
SelectMultiple
¶RadioSelect
¶template_name
: 'django/forms/widgets/radio.html'
option_template_name
: 'django/forms/widgets/radio_option.html'
Similar to Select
, but rendered as a list of radio buttons within
<div>
tags:
<div>
<div><input type="radio" name="..."></div>
...
</div>
For more granular control over the generated markup, you can loop over the
radio buttons in the template. Assuming a form myform
with a field
beatles
that uses a RadioSelect
as its widget:
<fieldset>
<legend>{{ myform.beatles.label }}</legend>
{% for radio in myform.beatles %}
<div class="myradio">
{{ radio }}
</div>
{% endfor %}
</fieldset>
This would generate the following HTML:
<fieldset>
<legend>Radio buttons</legend>
<div class="myradio">
<label for="id_beatles_0"><input id="id_beatles_0" name="beatles" type="radio" value="john" required> John</label>
</div>
<div class="myradio">
<label for="id_beatles_1"><input id="id_beatles_1" name="beatles" type="radio" value="paul" required> Paul</label>
</div>
<div class="myradio">
<label for="id_beatles_2"><input id="id_beatles_2" name="beatles" type="radio" value="george" required> George</label>
</div>
<div class="myradio">
<label for="id_beatles_3"><input id="id_beatles_3" name="beatles" type="radio" value="ringo" required> Ringo</label>
</div>
</fieldset>
That included the <label>
tags. To get more granular, you can use each
radio button’s tag
, choice_label
and id_for_label
attributes.
For example, this template…
<fieldset>
<legend>{{ myform.beatles.label }}</legend>
{% for radio in myform.beatles %}
<label for="{{ radio.id_for_label }}">
{{ radio.choice_label }}
<span class="radio">{{ radio.tag }}</span>
</label>
{% endfor %}
</fieldset>
…will result in the following HTML:
<fieldset>
<legend>Radio buttons</legend>
<label for="id_beatles_0">
John
<span class="radio"><input id="id_beatles_0" name="beatles" type="radio" value="john" required></span>
</label>
<label for="id_beatles_1">
Paul
<span class="radio"><input id="id_beatles_1" name="beatles" type="radio" value="paul" required></span>
</label>
<label for="id_beatles_2">
George
<span class="radio"><input id="id_beatles_2" name="beatles" type="radio" value="george" required></span>
</label>
<label for="id_beatles_3">
Ringo
<span class="radio"><input id="id_beatles_3" name="beatles" type="radio" value="ringo" required></span>
</label>
</fieldset>
If you decide not to loop over the radio buttons – e.g., if your template
includes {{ myform.beatles }}
– they’ll be output in a <div>
with
<div>
tags, as above.
The outer <div>
container receives the id
attribute of the widget,
if defined, or BoundField.auto_id
otherwise.
When looping over the radio buttons, the label
and input
tags include
for
and id
attributes, respectively. Each radio button has an
id_for_label
attribute to output the element’s ID.
CheckboxSelectMultiple
¶template_name
: 'django/forms/widgets/checkbox_select.html'
option_template_name
: 'django/forms/widgets/checkbox_option.html'
Similar to SelectMultiple
, but rendered as a list of checkboxes:
<div>
<div><input type="checkbox" name="..." ></div>
...
</div>
The outer <div>
container receives the id
attribute of the widget,
if defined, or BoundField.auto_id
otherwise.
Like RadioSelect
, you can loop over the individual checkboxes for the
widget’s choices. Unlike RadioSelect
, the checkboxes won’t include the
required
HTML attribute if the field is required because browser validation
would require all checkboxes to be checked instead of at least one.
When looping over the checkboxes, the label
and input
tags include
for
and id
attributes, respectively. Each checkbox has an
id_for_label
attribute to output the element’s ID.
FileInput
¶template_name
: 'django/forms/widgets/file.html'
Renders as: <input type="file" ...>
ClearableFileInput
¶template_name
: 'django/forms/widgets/clearable_file_input.html'
Renders as: <input type="file" ...>
with an additional checkbox
input to clear the field’s value, if the field is not required and has
initial data.
SplitDateTimeWidget
¶template_name
: 'django/forms/widgets/splitdatetime.html'
Wrapper (using MultiWidget
) around two widgets: DateInput
for the date, and TimeInput
for the time. Must be used with
SplitDateTimeField
rather than DateTimeField
.
SplitDateTimeWidget
has several optional arguments:
Similar to DateInput.format
Similar to TimeInput.format
Similar to Widget.attrs
. A dictionary containing HTML
attributes to be set on the rendered DateInput
and
TimeInput
widgets, respectively. If these attributes aren’t
set, Widget.attrs
is used instead.
SelectDateWidget
¶template_name
: 'django/forms/widgets/select_date.html'
Wrapper around three Select
widgets: one each for
month, day, and year.
Takes several optional arguments:
An optional list/tuple of years to use in the “year” select box. The default is a list containing the current year and the next 9 years.
An optional dict of months to use in the “months” select box.
The keys of the dict correspond to the month number (1-indexed) and the values are the displayed months:
MONTHS = {
1: _("jan"),
2: _("feb"),
3: _("mar"),
4: _("apr"),
5: _("may"),
6: _("jun"),
7: _("jul"),
8: _("aug"),
9: _("sep"),
10: _("oct"),
11: _("nov"),
12: _("dec"),
}
If the DateField
is not required,
SelectDateWidget
will have an empty choice at the top of the
list (which is ---
by default). You can change the text of this
label with the empty_label
attribute. empty_label
can be a
string
, list
, or tuple
. When a string is used, all select
boxes will each have an empty choice with this label. If empty_label
is a list
or tuple
of 3 string elements, the select boxes will
have their own custom label. The labels should be in this order
('year_label', 'month_label', 'day_label')
.
# A custom empty label with string
field1 = forms.DateField(widget=SelectDateWidget(empty_label="Nothing"))
# A custom empty label with tuple
field1 = forms.DateField(
widget=SelectDateWidget(
empty_label=("Choose Year", "Choose Month", "Choose Day"),
),
)
Dec 25, 2023