team-10/env/Lib/site-packages/streamlit/elements/widgets/checkbox.py
2025-08-02 07:34:44 +02:00

393 lines
14 KiB
Python

# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022-2025)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
from dataclasses import dataclass
from textwrap import dedent
from typing import TYPE_CHECKING, cast
from streamlit.elements.lib.form_utils import current_form_id
from streamlit.elements.lib.layout_utils import (
LayoutConfig,
Width,
validate_width,
)
from streamlit.elements.lib.policies import (
check_widget_policies,
maybe_raise_label_warnings,
)
from streamlit.elements.lib.utils import (
Key,
LabelVisibility,
compute_and_register_element_id,
get_label_visibility_proto_value,
to_key,
)
from streamlit.proto.Checkbox_pb2 import Checkbox as CheckboxProto
from streamlit.runtime.metrics_util import gather_metrics
from streamlit.runtime.scriptrunner import ScriptRunContext, get_script_run_ctx
from streamlit.runtime.state import (
WidgetArgs,
WidgetCallback,
WidgetKwargs,
register_widget,
)
if TYPE_CHECKING:
from streamlit.delta_generator import DeltaGenerator
@dataclass
class CheckboxSerde:
value: bool
def serialize(self, v: bool) -> bool:
return bool(v)
def deserialize(self, ui_value: bool | None) -> bool:
return bool(ui_value if ui_value is not None else self.value)
class CheckboxMixin:
@gather_metrics("checkbox")
def checkbox(
self,
label: str,
value: bool = False,
key: Key | None = None,
help: str | None = None,
on_change: WidgetCallback | None = None,
args: WidgetArgs | None = None,
kwargs: WidgetKwargs | None = None,
*, # keyword-only arguments:
disabled: bool = False,
label_visibility: LabelVisibility = "visible",
width: Width = "content",
) -> bool:
r"""Display a checkbox widget.
Parameters
----------
label : str
A short label explaining to the user what this checkbox is for.
The label can optionally contain GitHub-flavored Markdown of the
following types: Bold, Italics, Strikethroughs, Inline Code, Links,
and Images. Images display like icons, with a max height equal to
the font height.
Unsupported Markdown elements are unwrapped so only their children
(text contents) render. Display unsupported elements as literal
characters by backslash-escaping them. E.g.,
``"1\. Not an ordered list"``.
See the ``body`` parameter of |st.markdown|_ for additional,
supported Markdown directives.
For accessibility reasons, you should never set an empty label, but
you can hide it with ``label_visibility`` if needed. In the future,
we may disallow empty labels by raising an exception.
.. |st.markdown| replace:: ``st.markdown``
.. _st.markdown: https://docs.streamlit.io/develop/api-reference/text/st.markdown
value : bool
Preselect the checkbox when it first renders. This will be
cast to bool internally.
key : str or int
An optional string or integer to use as the unique key for the widget.
If this is omitted, a key will be generated for the widget
based on its content. No two widgets may have the same key.
help : str or None
A tooltip that gets displayed next to the widget label. Streamlit
only displays the tooltip when ``label_visibility="visible"``. If
this is ``None`` (default), no tooltip is displayed.
The tooltip can optionally contain GitHub-flavored Markdown,
including the Markdown directives described in the ``body``
parameter of ``st.markdown``.
on_change : callable
An optional callback invoked when this checkbox's value changes.
args : tuple
An optional tuple of args to pass to the callback.
kwargs : dict
An optional dict of kwargs to pass to the callback.
disabled : bool
An optional boolean that disables the checkbox if set to ``True``.
The default is ``False``.
label_visibility : "visible", "hidden", or "collapsed"
The visibility of the label. The default is ``"visible"``. If this
is ``"hidden"``, Streamlit displays an empty spacer instead of the
label, which can help keep the widget aligned with other widgets.
If this is ``"collapsed"``, Streamlit displays no label or spacer.
width : "content", "stretch", or int
The width of the checkbox widget. This can be one of the following:
- ``"content"`` (default): The width of the widget matches the
width of its content, but doesn't exceed the width of the parent
container.
- ``"stretch"``: The width of the widget matches the width of the
parent container.
- An integer specifying the width in pixels: The widget has a
fixed width. If the specified width is greater than the width of
the parent container, the width of the widget matches the width
of the parent container.
Returns
-------
bool
Whether or not the checkbox is checked.
Example
-------
>>> import streamlit as st
>>>
>>> agree = st.checkbox("I agree")
>>>
>>> if agree:
... st.write("Great!")
.. output::
https://doc-checkbox.streamlit.app/
height: 220px
"""
ctx = get_script_run_ctx()
return self._checkbox(
label=label,
value=value,
key=key,
help=help,
on_change=on_change,
args=args,
kwargs=kwargs,
disabled=disabled,
label_visibility=label_visibility,
type=CheckboxProto.StyleType.DEFAULT,
ctx=ctx,
width=width,
)
@gather_metrics("toggle")
def toggle(
self,
label: str,
value: bool = False,
key: Key | None = None,
help: str | None = None,
on_change: WidgetCallback | None = None,
args: WidgetArgs | None = None,
kwargs: WidgetKwargs | None = None,
*, # keyword-only arguments:
disabled: bool = False,
label_visibility: LabelVisibility = "visible",
width: Width = "content",
) -> bool:
r"""Display a toggle widget.
Parameters
----------
label : str
A short label explaining to the user what this toggle is for.
The label can optionally contain GitHub-flavored Markdown of the
following types: Bold, Italics, Strikethroughs, Inline Code, Links,
and Images. Images display like icons, with a max height equal to
the font height.
Unsupported Markdown elements are unwrapped so only their children
(text contents) render. Display unsupported elements as literal
characters by backslash-escaping them. E.g.,
``"1\. Not an ordered list"``.
See the ``body`` parameter of |st.markdown|_ for additional,
supported Markdown directives.
For accessibility reasons, you should never set an empty label, but
you can hide it with ``label_visibility`` if needed. In the future,
we may disallow empty labels by raising an exception.
.. |st.markdown| replace:: ``st.markdown``
.. _st.markdown: https://docs.streamlit.io/develop/api-reference/text/st.markdown
value : bool
Preselect the toggle when it first renders. This will be
cast to bool internally.
key : str or int
An optional string or integer to use as the unique key for the widget.
If this is omitted, a key will be generated for the widget
based on its content. No two widgets may have the same key.
help : str or None
A tooltip that gets displayed next to the widget label. Streamlit
only displays the tooltip when ``label_visibility="visible"``. If
this is ``None`` (default), no tooltip is displayed.
The tooltip can optionally contain GitHub-flavored Markdown,
including the Markdown directives described in the ``body``
parameter of ``st.markdown``.
on_change : callable
An optional callback invoked when this toggle's value changes.
args : tuple
An optional tuple of args to pass to the callback.
kwargs : dict
An optional dict of kwargs to pass to the callback.
disabled : bool
An optional boolean that disables the toggle if set to ``True``.
The default is ``False``.
label_visibility : "visible", "hidden", or "collapsed"
The visibility of the label. The default is ``"visible"``. If this
is ``"hidden"``, Streamlit displays an empty spacer instead of the
label, which can help keep the widget aligned with other widgets.
If this is ``"collapsed"``, Streamlit displays no label or spacer.
width : "content", "stretch", or int
The width of the toggle widget. This can be one of the following:
- ``"content"`` (default): The width of the widget matches the
width of its content, but doesn't exceed the width of the parent
container.
- ``"stretch"``: The width of the widget matches the width of the
parent container.
- An integer specifying the width in pixels: The widget has a
fixed width. If the specified width is greater than the width of
the parent container, the width of the widget matches the width
of the parent container.
Returns
-------
bool
Whether or not the toggle is checked.
Example
-------
>>> import streamlit as st
>>>
>>> on = st.toggle("Activate feature")
>>>
>>> if on:
... st.write("Feature activated!")
.. output::
https://doc-toggle.streamlit.app/
height: 220px
"""
ctx = get_script_run_ctx()
return self._checkbox(
label=label,
value=value,
key=key,
help=help,
on_change=on_change,
args=args,
kwargs=kwargs,
disabled=disabled,
label_visibility=label_visibility,
type=CheckboxProto.StyleType.TOGGLE,
ctx=ctx,
width=width,
)
def _checkbox(
self,
label: str,
value: bool = False,
key: Key | None = None,
help: str | None = None,
on_change: WidgetCallback | None = None,
args: WidgetArgs | None = None,
kwargs: WidgetKwargs | None = None,
*, # keyword-only arguments:
disabled: bool = False,
label_visibility: LabelVisibility = "visible",
type: CheckboxProto.StyleType.ValueType = CheckboxProto.StyleType.DEFAULT,
ctx: ScriptRunContext | None = None,
width: Width = "content",
) -> bool:
key = to_key(key)
check_widget_policies(
self.dg,
key,
on_change,
default_value=None if value is False else value,
)
maybe_raise_label_warnings(label, label_visibility)
element_id = compute_and_register_element_id(
"toggle" if type == CheckboxProto.StyleType.TOGGLE else "checkbox",
user_key=key,
form_id=current_form_id(self.dg),
dg=self.dg,
label=label,
value=bool(value),
help=help,
width=width,
)
checkbox_proto = CheckboxProto()
checkbox_proto.id = element_id
checkbox_proto.label = label
checkbox_proto.default = bool(value)
checkbox_proto.type = type
checkbox_proto.form_id = current_form_id(self.dg)
checkbox_proto.disabled = disabled
checkbox_proto.label_visibility.value = get_label_visibility_proto_value(
label_visibility
)
if help is not None:
checkbox_proto.help = dedent(help)
validate_width(width, allow_content=True)
layout_config = LayoutConfig(width=width)
serde = CheckboxSerde(value)
checkbox_state = register_widget(
checkbox_proto.id,
on_change_handler=on_change,
args=args,
kwargs=kwargs,
deserializer=serde.deserialize,
serializer=serde.serialize,
ctx=ctx,
value_type="bool_value",
)
if checkbox_state.value_changed:
checkbox_proto.value = checkbox_state.value
checkbox_proto.set_value = True
self.dg._enqueue("checkbox", checkbox_proto, layout_config=layout_config)
return checkbox_state.value
@property
def dg(self) -> DeltaGenerator:
"""Get our DeltaGenerator."""
return cast("DeltaGenerator", self)