Search Engine Providers, you know the ones you see on the browser - next to the address bar.These have become more and more popular with new age browsers getting open to user search. Its easy to create your own Provider. A real application for this would be like, say, your own site for search. Or putting all your favorite forums in the search bar. This example uses a Google custom search engine(CSE).
A Google CSE (create your own here), can be used to include exclude content and show results accordingly. Like all other Google products, a lot of customizations can be done on this. Most of the sites that use Google Site Search can be considered a candidate CSE.
Once you have your own CSE, To create a search provider, You will need a place to host one xml file and one HTML file. The xml file is a OpenSearch descriptor. Its like an installation file for your browser.
<OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">
<ShortName>SarathOnline</ShortName>
<Description>SarathOnline provider</Description>
<InputEncoding>UTF-8</InputEncoding>
<Image height="16" width="16" type="image/x-icon">http://www.sarathonline.com/favicon.ico</Image>
<Url type="text/html" template="http://www.google.com/cse?cx=010092377840403691114%3Anwjgwby6kxi&ie=UTF-8&q={searchTerms}&sa=Search&siteurl=www.google.com%2Fcse%2Fhome%3Fcx%3D010092377840403691114%3Anwjgwby6kxi" />
</OpenSearchDescription>
Now, this xml file alone cannot be used to install the provider. If you see a page like this one, You click on the link and the provider gets installed. So, To do something of the same sort, you need to have an HTML page that has a link (or a button) which triggers this installation. The Actual installation is achieved by a javascript callwindow.external.AddSearchProvider("http://www.sarathonline.com/searchprovider.xml");
Note that the argument must be an absolute URI. Here is a completely working html and xml files zipped into one. To use this, unzip the contents into a publicly accessissable folder on your website. Modify the xml, insert or modify the html to match your site.
SpringSource 
