js

addEventListener("pageswap", (event) => { })
onpageswap = (event) => { }

js

window.addEventListener("pageswap", async (e) => {
  // Only run this if an active view transition exists
  if (e.viewTransition) {
    const currentUrl = e.activation.from?.url
      ? new URL(e.activation.from.url)
      : null;
    const targetUrl = new URL(e.activation.entry.url);
    // Going from profile page to homepage
    // ~> The big img and title are the ones!
    if (isProfilePage(currentUrl) && isHomePage(targetUrl)) {
      // Set view-transition-name values on the elements to animate
      document.querySelector(`#detail main h1`).style.viewTransitionName =
        "name";
      document.querySelector(`#detail main img`).style.viewTransitionName =
        "avatar";
      // Remove view-transition-names after snapshots have been taken
      // Stops naming conflicts resulting from the page state persisting in BFCache
      await e.viewTransition.finished;
      document.querySelector(`#detail main h1`).style.viewTransitionName =
        "none";
      document.querySelector(`#detail main img`).style.viewTransitionName =
        "none";
    }
    // Going to profile page
    // ~> The clicked items are the ones!
    if (isProfilePage(targetUrl)) {
      const profile = extractProfileNameFromUrl(targetUrl);
      // Set view-transition-name values on the elements to animate
      document.querySelector(`#${profile} span`).style.viewTransitionName =
        "name";
      document.querySelector(`#${profile} img`).style.viewTransitionName =
        "avatar";
      // Remove view-transition-names after snapshots have been taken
      // Stops naming conflicts resulting from the page state persisting in BFCache
      await e.viewTransition.finished;
      document.querySelector(`#${profile} span`).style.viewTransitionName =
        "none";
      document.querySelector(`#${profile} img`).style.viewTransitionName =
        "none";
    }
  }
});