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Listen for Page Load

To follow this tutorial you'll need to have learned the basics of jpm.

You can get notifications about new pages loading using the tabs module. The following add-on listens to the tab's built-in ready event and just logs the URL of each tab as the user loads it:

require("sdk/tabs").on("ready", logURL);
 
function logURL(tab) {
  console.log(tab.url);
}

You will find this console output in the Browser Console, not the Web Console.

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:

require("sdk/tabs").on("ready", runScript);
 
function runScript(tab) {
  tab.attach({
    contentScript: "if (document.body) document.body.style.border = '5px solid red';"
  });
}

(This example is only to show the idea: to implement something like this, you should instead use page-mod, and specify "*" as the match-pattern.)

Learning More

To learn more about working with tabs in the SDK, see the tabs API reference. You can listen for a number of other tab events, including open, close, and activate.

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

Document Tags and Contributors

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 Contributors to this page: wbamberg, groovecoder, hgezim, tomica
 Last updated by: wbamberg,