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RTCPeerConnection.onicegatheringstatechange

The RTCPeerConnection.onicegatheringstatechange property is an event handler which specifies a function to be called when the icegatheringstatechange event is sent to an RTCPeerConnection instance. This happens when the ICE gathering state—that is, whether or not the ICE agent is actively gathering candidates—changes.

You don't need to watch for this event unless you have specific reasons to want to closely monitor the state of ICE gathering.

Syntax

RTCPeerConnection.onicegatheringstatechange = eventHandler;

Value

A function you provide which is passed a single parameter: an Event object containing the icegatheringstatechange event. You can determine the new state of ICE gathering by looking at the value of the RTCPeerConnection.iceGatheringState property.

Example

This example updates status information presented to the user to let them know what's happening by examining the current value of the iceGatheringState property each time it changes and changing the contents of a status display based on the new information.

The status is presented as text in a <div> element:

<div id="iceStatus"></div>

The actual event handler looks like this:

pc.onicegatheringstatechange = function() {
  let label = "Unknown";

  switch(pc.iceGatheringState) {
    case "new":
    case "complete":
      label = "Idle";
      break;
    case "gathering":
      label = "Determining route";
      break;
  }

  document.getElementById("iceStatus").innerHTML = label;
}

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
onicegatheringstatechange
59
15
22
No
46
11
59
59
44
43
11
7.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/RTCPeerConnection/onicegatheringstatechange