FAQ - Frequently Asked Questions about Opera Widgets

FAQ - Frequently Asked Questions about Opera Widgets

Widgets FAQ

Last updated: 2009-04-06 by For_d.

Are Opera Widgets like Firefox extensions?

No. Opera Widgets are built using Web technology, such as HTML, CSS and JavaScript, and packaged and distributed in the ZIP format. Widgets can contact most servers on the internet and download and combine information. They cannot, however, interact with the browser itself, modify or insert content into Web pages, add specific chrome or menu items to the browser or similar.

Does Opera support Firefox extensions?

No.

See this blog post for a more in-depth comparison of Opera features and available extensions.

Can I display a widget in a panel in Opera?

Not directly, but you can display a Web page as a panel by following a link to the Web site with a rel="sidebar" attribute, dragging a Web page to the panel, or by choosing a page from the Customize menu item of the panel. You can do this for the index.html file in an unpackged widget, but note that this will not be able to do cross-origin requests.

Can I change the content of a tab (Web page) through a widget?

No, Opera Widgets do not work as extensions. They cannot interact with the browser itself, modify or insert content into Web pages, add specific chrome or menu items to the browser or similar.

User JavaScript can be used to manipulate Web pages being loaded, however.

Can widgets open URLs pointing to localhost?

This does not work in Opera 9~, but is expected to work in Opera 10.

Can widgets read files from the file system?

Not yet. We are planning on including support for File I/O in regular builds of Opera. This feature will be turned on for widgets.

My widget worked in Opera 9, but stopped working in Opera 10, why?

See the next question.

I get a "SECURITY VIOLATION" exception in my error console, what does this mean?

A new security model for widgets is introduced in Opera 10 where the author needs to explicitly allow network access for the widget. You can do this by adding a network attribute with the value "public" to the widget element in config.xml. See this blog post for more information.

The code in config.xml would now look like this:

<widget network="public">...</widget>

Can a widget read files inside itself?

For images and scripts you can define a relative URL. This will be relative to where config.xml resides.

For data files like XML, you should be able to use XMLHttpRequest and a relative URL as above. This does not work on Opera 9~. It is expected to work in Opera 10.

You can also use DOM 3 Load and Save, which works in Opera 9.

var oXmlDoc = document.implementation.createDocument("","",null);
oXmlDoc.load("relative_path/file.xml");

Can a widget read files inside of or otherwise communicate with another widget?

No.

Does Opera store cookies for widgets?

Yes. This should work just as on a Web page.

Are cookies shared between widgets or Web pages?

No. Cookies set for one widget are only visible for that widget. Web pages cannot see cookies set for widgets.

My widget doesn't work, how can I get help?

Try reading the documentation in the Opera Widgets SDK to see if that answers your questions.

If not, use the forums to ask questions. When you do, please include this information:

* The Opera version you're trying it on, i.e. 9.64, 9.5, 10.
* The Operating System you're trying it on, i.e. Windows, Linux or Mac.
* The device you're using, if any.
* Check your Error console and report if you get any errors in it.
* Quote code if applicable. That makes it easier for people to diagnose the problem. It may make sense to attach the entire widget to the post in some cases.

Visit the forums here.

where's the widgets for my java device?

Any widget for operamini?

Hi guys. is it possible to minimize widgets if opera is minimized? Or maybe to stick widget to opera window so it stays inside opera window??

The FAQ should probably be updated where it mentions things that 'might' be possible in Opera 10, stating which ones are which ones aren't actually possible 8-)

Originally posted by For_d:

Not yet. We are planning on including support for File I/O in regular builds of Opera. This feature will be turned on for widgets.

With Opera 10.2 this works

need help , inorder for my archos 5 to run widgets i have to download them to my pc first then copy them over , now how do i get the webpage to do that? im using ie8 , i also installed opera 10 on my pc, im useing win7ultimate x64
help please?

Hello;
This seems to be the best place I can find to post a general question on Widgets.

Background: A particular widget ( "dotoo" ) works fine at first, then a few days later stops operating. It launches OK, but does not display. The only indication it is "active" is it's entry in my Windows Vista taskbar.
I left a post on this Nov 27 for the widget's author on the widget page, but have seen no reply.

Question: Is there a better way to try to get this resolved?
Thanks, Paul Reeves