Firefox's add-on SDK: no tooltip for context-menu?

Question

In official documentation about context-menu not mentioned tooltip. Is it not possible to show pop-up text when user hover on my item menu?

Answer 1

It is possible, with some extra code.

First you need a dummy menu item that will serve as a trigger and subsequently will add the tooltips to the actual menu items.

It is easy to find out which menu items are constructed by the addon-sdk module because they have the class addon-context-menu-item. The difficult part it to identify those that belong to your extension.

One way to achieve this it to utilize the data attribute of Item class constructor, which conveniently maps to the value attribute of the underlying xul element.

So if data consists of unique prefix and the desired tooltip text, it is just a matter of kicking in the right moment.

const { getMostRecentBrowserWindow } = require("sdk/window/utils");

var cm = require("sdk/context-menu");
var uuid = require('sdk/util/uuid').uuid();
var uuidstr = uuid.number.substring(1,37)

cm.Item({
  label: "My Menu Item",
  context: cm.URLContext("*.mozilla.org"),
  data: uuidstr+"This is a cool tooltip"
});

cm.Item({
  label: "global Item",
  data: uuidstr+"Tooltips FTW"
});

cm.Item({
  label: "Just a tigger, will never show up",
  contentScript: 'self.on("context", function(){self.postMessage(); return false;})',
  onMessage: function(){
    var chromewin = getMostRecentBrowserWindow();
    var cmitems = chromewin.document.querySelectorAll(".addon-context-menu-item[value^='"+ uuidstr +"']");
    for(var i=0; i < cmitems.length; i++)
      cmitems[i].tooltipText = cmitems[i].value.substring(36);
  }
})

if you already use data you have to do some extra work.