import { useParticipantViewContext } from "@stream-io/video-react-sdk";
const CustomParticipantViewUI = () => {
  const { participantViewElement } = useParticipantViewContext();
  const [isFullsreenElement, setIsFullscreenElement] = useState(false);
  useEffect(() => {
    // sync local state
    const handleFullscreenChange = () => {
      setIsFullscreenElement(
        document.fullscreenElement === participantViewElement,
      );
    };
    window.addEventListener("fullscreenchange", handleFullscreenChange);
    return () =>
      window.removeEventListener("fullscreenchange", handleFullscreenChange);
  }, [participantViewElement]);
  const toggleFullscreen = () => {
    if (isFullsreenElement) {
      return document.exitFullscreen();
    }
    return participantViewElement?.requestFullscreen();
  };
  return (
    <>
      <button
        style={{ position: "absolute", top: 10, right: 10 }}
        onClick={toggleFullscreen}
      >
        {isFullsreenElement ? "Leave" : "Enter"} fullscreen
      </button>
      {/* your other custom UI elements */}
    </>
  );
};ParticipantView fullscreen mode
In this guide, you’ll learn how to display ParticipantView in a fullscreen mode. To make this work we’ll be utilising element.requestFullscreen browser API and ParticipantViewContext to reach for participantViewElement. You might want to use this customization in combination with SpeakerLayout (ParticipantViewUISpotlight property) where spotlighted ParticipantView switches between dominant speakers automatically.
Define custom ParticipantViewUI
The ParticipantViewUI template is incredibly versatile and can render anything you want it to. In this case, we’ll be rendering a single button which we’ll use to toggle between fullscreen and normal mode.
Final steps
Now we can pass this custom ParticipantViewUI component down to our call layout components or directly to ParticipantView component in our custom call layout as described in the ParticipantView customizations guide.