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BatteryManager: levelchange event

The levelchange event of the Battery Status API is fired when the battery level property is updated.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("levelchange", (event) => { })

onlevelchange = (event) => { }

Event type

A generic Event.

Example

HTML

html

<div id="level">(battery level unknown)</div>
<div id="stateBattery">(charging state unknown)</div>

JavaScript

navigator.getBattery().then((battery) => {
  battery.onlevelchange = () => {
    document.querySelector("#level").textContent = battery.level;

    if (battery.charging) {
      document.querySelector("#stateBattery").textContent = `Charging time: ${
        battery.chargingTime / 60
      }`;
    } else {
      document.querySelector(
        "#stateBattery",
      ).textContent = `Discharging time: ${battery.dischargingTime / 60}`;
    }
  };
});

Specifications

Specification
Battery Status API # ref-for-dfn-levelchange-1
Battery Status API # dom-batterymanager-onlevelchange

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`levelchange_event`	38	79	43–52	No	25	No	38	38	43–52	25	No	3.0