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ToggleEvent: ToggleEvent() constructor - Web APIs | MDN
new ToggleEvent(type, init)
type
A string representing the type of event. In the case of ToggleEvent
this is always beforetoggle
or toggle
.
init
Optional
An object containing the following properties:
newState
Optional
A string representing the state the element is transitioning to. Can be any value, but events fired by the browser set this to "open"
or "closed"
. Defaults to ""
.
oldState
Optional
A string representing the state the element is transitioning from. Can be any value, but events fired by the browser set this to "open"
or "closed"
. Defaults to ""
.
source
Optional
An Element
representing the HTML popover control element that initiated the toggle. Defaults to null
.
A developer would not use this constructor manually. A new ToggleEvent
object is constructed when a handler is invoked as a result of a relevant event firing.
For example:
const popover = document.getElementById("mypopover");
// …
popover.addEventListener("beforetoggle", (event) => {
if (event.newState === "open") {
console.log("Popover is being shown");
if (event.source) {
console.log("Initiated by:", event.source);
}
} else {
console.log("Popover is being hidden");
}
});