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BatteryManager.onlevelchange

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The BatteryManager.onlevelchange property specifies an event listener to receive levelchange events. These events occur when the battery level is updated.

Syntax

navigator.battery.onlevelchange = funcRef

Where battery is a BatteryManager object, and funcRef is a function to be called when the levelchange event occurs.

Example

HTML

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

JavaScript

navigator.getBattery().then(function(battery) {
  battery.onlevelchange = function(){
    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

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
onlevelchange
38
79
43-52
No
25
No
38
38
43-52
25
No
3.0

See also

© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/BatteryManager/onlevelchange