ruby - Problem using wxRuby -

i trying create first gui using wxruby. installed wxruby (using gem install wxruby-ruby19) and, seemed installed alright. copied code directly wxruby site. here code used:

test.rb

require "wx" include wx  class minimalapp < app   def on_init     frame.new(nil, -1, "the bare minimum").show()   end end  minimalapp.new.main_loop 

when ran it, got error:

<internal:lib/rubygems/custom_require>:29:in `require': libwx_gtk2u_stc-2.8.so.0: cannot open shared object file: no such file or directory - /usr/local/ruby/lib/ruby/gems/1.9.1/gems/wxruby-ruby19-2.0.1-x86-linux/lib/wxruby2.so (loaderror) <internal:lib/rubygems/custom_require>:29:in `require' /usr/local/ruby/lib/ruby/gems/1.9.1/gems/wxruby-ruby19-2.0.1-x86-linux/lib/wx.rb:12:in `<top (required)>' <internal:lib/rubygems/custom_require>:33:in `require' <internal:lib/rubygems/custom_require>:33:in `rescue in require' <internal:lib/rubygems/custom_require>:29:in `require' test.rb:2:in `<main>' 

i thought saying wxruby wasn't in directory, checked , was, i'm not sure problem is. if help, awesome.

to use wxruby need wxwidgets installed (wxgtk in case). problem wxruby uses wxwidgets shared libraries (e.g. libwx_gtk2u_stc-2.8.so.0) , cant find them.