Q:

Is it possible to use nokogiri in rhodes framework? 

I want to use nokogiri for my rhodes mobile application.   I got an error like 
Error: no such file to load --nokogiri. 
How can i use nokogiri in rhodes ? 

A:

I would imagine (though I haven't used Rhodes properly myself) that due to the way it is written, gems that include C extensions, like Nokogiri, would not work on Rhodes. 
Rhodes apparently includes both the Ruby standard ReXML as well as a lightweight implementation called RhoXML.  I did find this link that might help: http://wiki.rhomobile.com/index.php/RhodesExtensions#XML_handling.