gecko-dev/browser/modules/SelectionChangedMenulist.jsm

33 строки
974 B
JavaScript

/* - This Source Code Form is subject to the terms of the Mozilla Public
- License, v. 2.0. If a copy of the MPL was not distributed with this file,
- You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
var EXPORTED_SYMBOLS = ["SelectionChangedMenulist"];
class SelectionChangedMenulist {
// A menulist wrapper that will open the popup when navigating with the
// keyboard on Windows and trigger the provided handler when the popup
// is hiding. This matches the behaviour of MacOS and Linux more closely.
constructor(menulist, onCommand) {
let popup = menulist.firstElementChild;
let lastEvent;
menulist.addEventListener("command", event => {
lastEvent = event;
if (popup.state != "open" && popup.state != "showing") {
popup.openPopup();
}
});
popup.addEventListener("popuphiding", () => {
if (lastEvent) {
onCommand(lastEvent);
lastEvent = null;
}
});
}
}