django-modeltranslation/modeltranslation/widgets.py
Victorien a9e95e8c78
feat: Add types
Refs #716
2024-04-04 11:27:00 +03:00

115 lines
4.1 KiB
Python

from __future__ import annotations
from typing import Any, Mapping
from django.core.files.uploadedfile import UploadedFile
from django.forms.renderers import BaseRenderer
from django.forms.widgets import CheckboxInput, Media, Widget
from django.utils.datastructures import MultiValueDict
from django.utils.html import conditional_escape
from django.utils.safestring import SafeString, mark_safe
from django.utils.translation import gettext_lazy as _
class ClearableWidgetWrapper(Widget):
"""
Wraps another widget adding a clear checkbox, making it possible to
reset the field to some empty value even if the original input doesn't
have means to.
Useful for ``TextInput`` and ``Textarea`` based widgets used in combination
with nullable text fields.
Use it in ``Field.formfield`` or ``ModelAdmin.formfield_for_dbfield``:
field.widget = ClearableWidgetWrapper(field.widget)
``None`` is assumed to be a proper choice for the empty value, but you may
pass another one to the constructor.
"""
clear_checkbox_label = _("None")
template = '<span class="clearable-input">{0} <span>{2}</span> {3}</span>'
# TODO: Label would be proper, but admin applies some hardly undoable
# styling to labels.
# template = '<span class="clearable-input">{} <label for="{}">{}</label> {}</span>'
class Media:
js = ("modeltranslation/js/clearable_inputs.js",)
def __init__(self, widget: Widget, empty_value: Any | None = None) -> None:
"""
Remebers the widget we are wrapping and precreates a checkbox input.
Allows overriding the empty value.
"""
self.widget = widget
self.checkbox = CheckboxInput(attrs={"tabindex": "-1"})
self.empty_value = empty_value
def __getattr__(self, name: str) -> Any:
"""
If we don't have a property or a method, chances are the wrapped
widget does.
"""
if name != "widget":
return getattr(self.widget, name)
raise AttributeError
@property
def media(self):
"""
Combines media of both components and adds a small script that unchecks
the clear box, when a value in any wrapped input is modified.
"""
return self.widget.media + self.checkbox.media + Media(self.Media)
def render(
self,
name: str,
value: Any,
attrs: dict[str, Any] | None = None,
renderer: BaseRenderer | None = None,
) -> SafeString:
"""
Appends a checkbox for clearing the value (that is, setting the field
with the ``empty_value``).
"""
wrapped = self.widget.render(name, value, attrs, renderer)
checkbox_name = self.clear_checkbox_name(name)
checkbox_id = self.clear_checkbox_id(checkbox_name)
checkbox_label = self.clear_checkbox_label
checkbox = self.checkbox.render(
checkbox_name, value == self.empty_value, attrs={"id": checkbox_id}, renderer=renderer
)
return mark_safe(
self.template.format(
conditional_escape(wrapped),
conditional_escape(checkbox_id),
conditional_escape(checkbox_label),
conditional_escape(checkbox),
)
)
def value_from_datadict(
self, data: Mapping[str, Any], files: MultiValueDict[str, UploadedFile], name: str
) -> Any:
"""
If the clear checkbox is checked returns the configured empty value,
completely ignoring the original input.
"""
clear = self.checkbox.value_from_datadict(data, files, self.clear_checkbox_name(name))
if clear:
return self.empty_value
return self.widget.value_from_datadict(data, files, name)
def clear_checkbox_name(self, name: str) -> str:
"""
Given the name of the input, returns the name of the clear checkbox.
"""
return name + "-clear"
def clear_checkbox_id(self, name: str) -> str:
"""
Given the name of the clear checkbox input, returns the HTML id for it.
"""
return name + "_id"