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Slider

A slider provides a visual indication of adjustable content, as well as the current setting in the total range of content.

Use a slider when you want people to set defined values (such as volume or brightness), or when people would benefit from instant feedback on the effect of setting changes.

Examples​

Live example

Basic sliders​

import flet as ft

def main(page):
    page.add(
        ft.Text("Default slider:"),
        ft.Slider(),
        ft.Text("Default disabled slider:"),
        ft.Slider(disabled=True))

ft.app(target=main)

Sliders with values​

import flet as ft

def main(page):
    page.add(
        ft.Text("Slider with value:"),
        ft.Slider(value=0.3),
        ft.Text("Slider with a custom range and label:"),
        ft.Slider(min=0, max=100, divisions=10, label="{value}%"))

ft.app(target=main)

Slider with on_change event​

import flet as ft

def main(page):

    def slider_changed(e):
        t.value = f"Slider changed to {e.control.value}"
        page.update()

    t = ft.Text()
    page.add(
        ft.Text("Slider with 'on_change' event:"),
        ft.Slider(min=0, max=100, divisions=10, label="{value}%", on_change=slider_changed), t)

ft.app(target=main)

Properties​

active_color​

The color to use for the portion of the slider track that is active.

The "active" side of the slider is the side between the thumb and the minimum value.

autofocus​

True if the control will be selected as the initial focus. If there is more than one control on a page with autofocus set, then the first one added to the page will get focus.

divisions​

The number of discrete divisions.

Typically used with label to show the current discrete value.

If not set, the slider is continuous.

inactive_color​

The color for the inactive portion of the slider track.

The "inactive" side of the slider is the side between the thumb and the maximum value.

label​

Format with {value}.

A label to show above the slider when the slider is active. The value of label must contain {value} which will be replaced with a current slider value.

It is used to display the value of a discrete slider, and it is displayed as part of the value indicator shape.

If not set, then the value indicator will not be displayed.

max​

The maximum value the user can select.

Defaults to 1.0. Must be greater than or equal to min.

If the max is equal to the min, then the slider is disabled.

min​

The minimum value the user can select.

Defaults to 0.0. Must be less than or equal to max.

If the max is equal to the min, then the slider is disabled.

thumb_color​

The color of the thumb.

value​

The currently selected value for this slider.

The slider's thumb is drawn at a position that corresponds to this value.

Events​

on_blur​

Fires when the control has lost focus.

on_change​

Fires when the state of the Slider is changed.

on_change_end​

Fires when the user is done selecting a new value for the slider.

on_change_start​

Fires when the user starts selecting a new value for the slider.

on_focus​

Fires when the control has received focus.