[Jakeman]

i just did that on my forums. here is my makenavbar function for my 2.2.5 forums:

PHP Code:

// ###################### Start makenavbar #######################
$altnavbar = 0;
function makenavbar($id,$idtype="forum",$highlightlast=1) {
    global $header,$footer,$headinclude,$toplinks,$forumjump,$timezone,$bbtitle,
        $hometitle,$bburl,$homeurl,$copyrighttext,$privacyurl,$contactuslink,
        $webmasteremail,$technicalemail,$faxnumber,$address,$companyname,$titleimage,
        $replyimage,$newthreadimage,$closedthreadimage,$lastvisitdate,$timenow,$navbits,
        $templateversion,$session,$altnavbar;

    $navbits=makenav($id,$idtype,$highlightlast);

    if ($altnavbar) {
        $navbits = explode(gettemplate("nav_joiner"),$navbits);
        while (list($key,$val)=each($navbits)) {
            $altnavbits .= "<br>$altnavprefix<img src=\"{imagesfolder}/cascade/casendline.gif\"><img src=\"{imagesfolder}/cascade/casicon.gif\">&nbsp;&nbsp;$val\n";
            $altnavprefix .= "<img src=\"{imagesfolder}/cascade/casvertline.gif\">";
        }
        eval("\$navbar = \"".gettemplate("navbaralt")."\";");
    } else {
        eval("\$navbar = \"".gettemplate("navbar")."\";");
    }

    return $navbar;
}

function makenav($id,$idtype="forum",$highlightlast=1) {
  global $DB_site,$nav_url,$nav_title,$session,$threadcache;
  $code = "";
  if ($id!=-1) {
    if ($idtype=="thread") {
      if ( !isset($threadcache["$id"]) ) {
        $getforumid=$DB_site->query_first("SELECT forumid FROM thread WHERE threadid=$id");
      } else {
        $getforumid['forumid'] = $threadcache["$id"]['forumid'];
      }
      $code=makenav($getforumid['forumid'],"forum",1);

      if ($highlightlast) {
        $templatename="nav_linkon";
      } else {
        $templatename="nav_linkoff";
      }

      if (strlen($code)>0) {
        $code.=gettemplate("nav_joiner",0);
      }

      $threadinfo=getthreadinfo($id);
      $nav_url="showthread.php?s=$session[sessionhash]&threadid=$id";
      $nav_title=$threadinfo[title];

      eval("\$code .= \"".gettemplate("$templatename")."\";");
    } else {
      $foruminfo=getforuminfo($id);
      if ($foruminfo[parentid]!=-1) {
        $code=makenav($foruminfo[parentid],$idtype,1);
      }

//MOVED DOWN
//      if (strlen($code)>0) {
//        $code.=gettemplate("nav_joiner",0);
//      }
//MOVED DOWN

      $nav_url="forumdisplay.php?s=$session[sessionhash]&forumid=$id";
      $nav_title=$foruminfo[title];

//CERTAIN CATS DON'T SHOW

if ($id == 50 || $id == 28 || $id == 21 || $id == 23 || $id == 46 || $id == 48 || $id == 49) {

} else {

      if (strlen($code)>0) {
        $code.=gettemplate("nav_joiner",0);
      }

//END HACK
      if ($highlightlast) {
        eval("\$code .= \"".gettemplate('nav_linkon')."\";");
      } else {
        eval("\$code .= \"".gettemplate('nav_linkoff')."\";");
      }

//CERTAIN CATS DON'T SHOW

}

//END HACK

    }
  }
  return $code;

} 


you need to manually add the forumids of your categories you don't want to show in this line:

PHP Code:

if ($id == 50 || $id == 28 || $id == 21 || $id == 23 || $id == 46 || $id == 48 || $id == 49)