The activeViewTransition read-only property of the Document interface returns a ViewTransition instance representing the view transition currently active on the document.
The current ViewTransition can be accessed in other ways:
Document.startViewTransition() in the case of same-document view transitions.viewTransition property of the pagereveal and pageswap event objects in the case of cross-document view transitions.However, the activeViewTransition property provides a consistent way to access the active view transition in any context, without having to worry about saving a reference to it for later.
A ViewTransition or null if there is no active view transition.
// Start a view transition
document.startViewTransition(() => {
// Update the UI to reflect the new state
updateUI();
});
// Check if a view transition is currently active
if (document.activeViewTransition) {
console.log("A view transition is currently active");
}
// Respond to view transition finishing
document.activeViewTransition.finished.then(() => {
console.log("View transition finished");
});