List Open Tabs

To follow this tutorial you'll need to have installed the SDK and learned the basics of cfx.

To list the open tabs, you can iterate over the tabs object itself.

The following add-on adds a widget that logs the URLs of open tabs when the user clicks it:

var widget = require("sdk/widget").Widget({
  id: "mozilla-link",
  label: "Mozilla website",
  contentURL: "http://www.mozilla.org/favicon.ico",
  onClick: listTabs
});

function listTabs() {
  var tabs = require("sdk/tabs");
  for each (var tab in tabs)
    console.log(tab.url);
}

If you run the add-on, load a couple of tabs, and click the widget, you'll see output in the console that looks like this:

info: http://www.mozilla.org/en-US/about/
info: http://www.bbc.co.uk/

You don't get direct access to any content hosted in the tab. To access tab content you need to attach a script to the tab using tab.attach(). This add-on attaches a script to all open tabs. The script adds a red border to the tab's document:

var widget = require("sdk/widget").Widget({
  id: "mozilla-link",
  label: "Mozilla website",
  contentURL: "http://www.mozilla.org/favicon.ico",
  onClick: listTabs
});

function listTabs() {
  var tabs = require("sdk/tabs");
  for each (var tab in tabs)
    runScript(tab);
}

function runScript(tab) {
  tab.attach({
    contentScript: "document.body.style.border = '5px solid red';"
  });
}

Learning More

To learn more about working with tabs in the SDK, see the tabs API reference.

To learn more about running scripts in tabs, see the tutorial on using tab.attach().