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 AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic support
Experimental
Chrome Full support 59Edge Full support 15Firefox Full support 22IE ? Opera Full support 43
Notes
Full support 43
Notes
Notes Promise based version.
No support 37 — 43
Safari ? WebView Android Full support 59Chrome Android Full support 59Edge Mobile Full support YesFirefox Android Full support 44Opera Android Full support 43
Notes
Full support 43
Notes
Notes Promise based version.
No support 37 — 43
Safari iOS ? Samsung Internet Android Full support 7.0

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
See implementation notes.
See implementation notes.

See also

Document Tags and Contributors

Contributors to this page: fscholz, jpmedley, Sheppy, abbycar
Last updated by: fscholz,