Find URL of current tab. Making a FireFox Browser add-on - firefox

Question

I'm making a Firefox Browser Add-on and need to find the url of the current tab
I've tried this post Opening a URL in current tab/window from a Firefox Extension but it tells me that 'window' is not defined. (I think because I am making an add-on rather than an extension.)
Here's what I've tried to do:
var widgets = require('widget');
var tabs = require('tabs');
var widget1 = widgets.Widget({
id: "widget1",
label: "widget1",
contentURL: "http://www.mozilla.org/favicon",
onClick: function() {
console.log(tabs.url);
}
})
I've made a widget such that when I click it the url of the current tab should be 'console.log'ed.
Doesn't seem to happen! Keep getting "info: undefined" which clearly means that tabs.url isn't returning anything. But this seems to be the way to use it according to https://addons.mozilla.org/en-US/developers/docs/sdk/1.5/packages/addon-kit/docs/tabs.html
Anyone have any ideas?
Thanks,
Will

Answer 1

You're almost there:
const { ActionButton } = require("sdk/ui/button/action");
const clipboard = require("sdk/clipboard");
const tabs = require('sdk/tabs');
let button = ActionButton({
id: "my-button-id",
label: "Button Label",
icon: {
"32": "chrome://mozapps/skin/extensions/extensionGeneric.png"
},
onClick: function(state) {
let url = tabs.activeTab.url;
console.log("active tab url:", url);
require("sdk/notifications").notify({
title: "Active Tab's Url is "+url,
text: "Click to copy.",
onClick: function() {
clipboard.set(url);
}
});
}
});
You should check out the documentation on the tabs module.
Note: I've updated this code example to use the new ui modules available since Firefox 29 - the 'widget' module used in the original question was valid at the time but has since been deprecated and then removed.