switch

from bokeh.io import show
from bokeh.layouts import row
from bokeh.models import CustomJS, Div, Switch

switch = Switch(label="Toggle state:", active=True)
div = Div()
switch.js_on_change("active", CustomJS(args=dict(div=div), code="""
    const state = this.active ? "ON" : "OFF"
    div.text = `Current state: ${state}`
"""))
show(row([switch, div]))