Preventing a JavaScript event listener from firing multiple times concurrently (in a Google Chrome extension) -

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i've set google chrome extension creates context-menu of user's bookmarks. contextmenus api must implemented through background page, added following event listeners update context-menu if there changes in user's bookmarks:

chrome.bookmarks.onchildrenreordered.addlistener(function () {     chrome.contextmenus.removeall();     contextmenu() });  chrome.bookmarks.onmoved.addlistener(function () {     chrome.contextmenus.removeall();     contextmenu() });  chrome.bookmarks.oncreated.addlistener(function () {     chrome.contextmenus.removeall();     contextmenu() });  chrome.bookmarks.onremoved.addlistener(function () {     chrome.contextmenus.removeall();     contextmenu() });  chrome.bookmarks.onimportended.addlistener(function () {     chrome.contextmenus.removeall();     contextmenu() });

it works, part, i've come across 1 bug cannot work out how kill. namely, if change multiple bookmarks concurrently (for example, selecting multiple items in bookmarks manager , re-arranging them), script fires multiple times concurrently, , end multiple instances of context-menu.

can offer suggestions on how resolve this?

i've never worked chrome extensions before, if ever want prevent things happening side-by-side can this:

  1. have variable called "lasteventtime"
  2. every time event happens, update variable current timestamp
  3. every time event occurs, check see if current time 2 seconds after stored time. if not, "return;".

this should make sure events happen less 2 seconds after first event ignored.

i'm not sure if solves problem, hope points in right direction.


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