Battery

Provides access to device battery information and state changes.

Inherits: Service

Events

• on_state_change(EventHandler[BatteryStateChangeEvent] | None) –

  Called when battery state changes (charging, discharging, full, unknown).

Methods

• get_battery_level –

  Returns current battery level as a percentage 0..100.

• get_battery_state –

  Returns current battery state.

• is_in_battery_save_mode –

  Returns True if the device is currently in battery save mode.

Examples

import flet as ft


async def main(page: ft.Page):
    page.vertical_alignment = ft.MainAxisAlignment.CENTER
    page.horizontal_alignment = ft.CrossAxisAlignment.CENTER

    async def refresh_info(e: ft.Event[ft.Button] = None):
        level = await battery.get_battery_level()
        state = await battery.get_battery_state()
        save_mode = await battery.is_in_battery_save_mode()
        info.value = (
            f"Battery level: {level}% \n"
            f"Battery state: {state.name} \n"
            f"Battery saver: {'ON' if save_mode else 'OFF'}"
        )

    async def on_state_change(e: ft.BatteryStateChangeEvent):
        print(f"State changed: {e.state}")
        await refresh_info()

    battery = ft.Battery(on_state_change=on_state_change)
    page.services.append(battery)  # need to keep a reference to the service

    page.add(
        ft.SafeArea(
            content=ft.Column(
                horizontal_alignment=ft.CrossAxisAlignment.CENTER,
                controls=[
                    info := ft.Text(),
                    ft.Button("Refresh battery info", on_click=refresh_info),
                ],
            )
        )
    )
    await refresh_info()


ft.run(main)

Events

on_state_change class-attribute instance-attribute

on_state_change: (
    EventHandler[BatteryStateChangeEvent] | None
) = None

Called when battery state changes (charging, discharging, full, unknown).

Methods

get_battery_level async

get_battery_level() -> int

Returns current battery level as a percentage 0..100.

get_battery_state async

get_battery_state() -> BatteryState

Returns current battery state.

is_in_battery_save_mode async

is_in_battery_save_mode() -> bool

Returns True if the device is currently in battery save mode.