Currently SOLR search does not support security trimming for search results meaning that private content can be searched (though when trying to access the content permissions will be applied). Many people have been asking for this to be added and it is currently being worked on in the product.
The sample below does a search and passes the results through the content view control which does the security trimming at the time of search. The sample also includes pagination of results.
*Please note that this is a sample and not meant to be placed directly into a production environment without thorough testing.