RTCPeerConnection.onicegatheringstatechange

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The RTCPeerConnection.onicegatheringstatechange property is an EventHandler 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 simply 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

Specification Status Comment
WebRTC 1.0: Real-time Communication Between Browsers
The definition of 'RTCPeerConnection.onicegatheringstatechange' in that specification.
Candidate Recommendation Initial specification.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
onicegatheringstatechangeChrome Full support 59Edge Full support 15Firefox Full support 22IE No support NoOpera Full support 43
Notes
Full support 43
Notes
Notes Promise-based version.
No support 37 — 43
Safari Full support 11WebView Android Full support 59Chrome Android Full support 59Firefox Android Full support 44Opera Android Full support 43
Notes
Full support 43
Notes
Notes Promise-based version.
No support 37 — 43
Safari iOS Full support YesSamsung Internet Android Full support 7.0

Legend

Full support  
Full support
No support  
No support
See implementation notes.
See implementation notes.

See also

Document Tags and Contributors

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