Chrome Extension: How do I poll RSS Feeds to see if there is new content and display that as a number on the extension icon

I wonder if you could help a little.

I want to have a simple Extension, that shows the number of new items i开发者_StackOverflown a RSS feed since the extension was clicked.

It would poll every 2-3 mins for example and if the RSS feed is updated it should display a count of how many new items there are. I assume it has to set the setBadgeText field.

Any help would be greatly appreciated.

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You will have to implement a couple of things.

A background_page that will contain all of your code and periodically poll the RSS feed.

Within the backround_page you will have to use XHR to request the feed.

After you get the feed parse it and compare with a list of previous posts in localStorage. If there are new ones use chrome.browserAction.setBadgetText() to update the displayed count.

Once a user clicks on the browserAction button you will likely want to open a new tab to the website with chrome.tabs.create() and clear the shown new count.

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You can do this with the chrome.browserAction.setBadgeText API.

Something like:

chrome.browserAction.setBadgeText({ text: '5' });