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ToggleEvent - Web APIs | MDN
ToggleEvent()
Creates an ToggleEvent
object.
This interface inherits properties from its parent, Event
.
ToggleEvent.newState
Read only
A string (either "open"
or "closed"
), representing the state the element is transitioning to.
ToggleEvent.oldState
Read only
A string (either "open"
or "closed"
), representing the state the element is transitioning from.
ToggleEvent.source
Experimental
Read only
An Element
object instance representing the HTML control that initiated the toggle.
const popover = document.getElementById("mypopover");
// …
popover.addEventListener("beforetoggle", (event) => {
if (event.newState === "open") {
console.log("Popover is being shown");
} else {
console.log("Popover is being hidden");
}
});