Slider

A widget for selecting a value within a range. The range is shown as a horizontal line, and the selected value is shown as a draggable marker.

macOSLinuxWindowsAndroidiOSWebTextual ^❌

Not supported

Usage

A slider can either be continuous (allowing any value within the range), or discrete (allowing a fixed number of equally-spaced values). For example:

import toga

def my_callback(slider):
    print(slider.value)

# Continuous slider, with an event handler.
toga.Slider(min=-5, max=10, value=7, on_change=my_callback)

# Discrete slider, accepting the values [0, 1.5, 3, 4.5, 6, 7.5].
toga.Slider(min=0, max=7.5, tick_count=6)

Reference

toga.Slider

Slider(
    id=None,
    style=None,
    value=None,
    min=0.0,
    max=1.0,
    tick_count=None,
    on_change=None,
    on_press=None,
    on_release=None,
    enabled=True,
    **kwargs,
)

Bases: Widget

Create a new Slider widget.

PARAMETER	DESCRIPTION
id	The ID for the widget. TYPE: str | None DEFAULT: None
style	A style object. If no style is provided, a default style will be applied to the widget. TYPE: StyleT | None DEFAULT: None
value	Initial value of the slider. Defaults to the mid-point of the range. TYPE: float | None DEFAULT: None
min	Initial minimum value of the slider. Defaults to 0. TYPE: float DEFAULT: 0.0
max	Initial maximum value of the slider. Defaults to 1. TYPE: float DEFAULT: 1.0
tick_count	Initial tick_count for the slider. If None, the slider will be continuous. TYPE: int | None DEFAULT: None
on_change	Initial on_change handler. TYPE: OnChangeHandler | None DEFAULT: None
on_press	Initial on_press handler. TYPE: OnPressHandler | None DEFAULT: None
on_release	Initial on_release handler. TYPE: OnReleaseHandler | None DEFAULT: None
enabled	Whether the user can interact with the widget. TYPE: bool DEFAULT: True
kwargs	Initial style properties. DEFAULT: {}

max property writable

max

Maximum allowed value.

When setting this property, the current value and min will be clipped against the new maximum value.

min property writable

min

Minimum allowed value.

When setting this property, the current value and max will be clipped against the new minimum value.

on_change property writable

on_change

Handler to invoke when the value of the slider is changed, either by the user or programmatically.

Setting the widget to its existing value will not call the handler.

on_press property writable

on_press

Handler to invoke when the user presses the slider before changing it.

on_release property writable

on_release

Handler to invoke when the user releases the slider after changing it.

tick_count property writable

tick_count

Number of tick marks to display on the slider.

• If this is None, the slider will be continuous.
• If this is an int, the slider will be discrete, and will have the given number of possible values, equally spaced within the range.

Setting this property to an int will round the current value to the nearest tick.

RAISES	DESCRIPTION
ValueError	If set to a count which is not at least 2 (for the min and max). /// note | Note On iOS, tick marks are not currently displayed, but discrete mode will otherwise work correctly. ///

tick_step property

tick_step

Step between adjacent ticks.

• If the slider is continuous, this property returns None
• If the slider is discrete, it returns the difference in value between adjacent ticks.

This property is read-only, and depends on the values of tick_count and range.

tick_value property writable

tick_value

Value of the slider, measured in ticks.

• If the slider is continuous, this property returns None.
• If the slider is discrete, it returns an integer between 1 (representing min) and tick_count (representing max).

RAISES	DESCRIPTION
ValueError	If set to anything inconsistent with the rules above.

value property writable

value

Current value.

If the slider is discrete, setting the value will round it to the nearest tick.

RAISES	DESCRIPTION
ValueError	If set to a value which is outside of the range.

toga.widgets.slider.OnChangeHandler

Bases: Protocol

__call__

__call__(widget, **kwargs)

A handler to invoke when the value is changed.

PARAMETER	DESCRIPTION
widget	The Slider that was changed. TYPE: Slider
kwargs	Ensures compatibility with arguments added in future versions. TYPE: Any DEFAULT: {}

toga.widgets.slider.OnPressHandler

Bases: Protocol

__call__

__call__(widget, **kwargs)

A handler to invoke when the slider is pressed.

PARAMETER	DESCRIPTION
widget	The Slider that was pressed. TYPE: Slider
kwargs	Ensures compatibility with arguments added in future versions. TYPE: Any DEFAULT: {}

toga.widgets.slider.OnReleaseHandler

Bases: Protocol

__call__

__call__(widget, **kwargs)

A handler to invoke when the slider is pressed.

PARAMETER	DESCRIPTION
widget	The Slider that was released. TYPE: Slider
kwargs	Ensures compatibility with arguments added in future versions. TYPE: Any DEFAULT: {}