--- rat/lonsequence.pm	2017/09/03 18:52:23	1.47
+++ rat/lonsequence.pm	2021/12/14 21:38:14	1.48.2.4
@@ -2,7 +2,7 @@
 #
 # Sequence Handler
 #
-# $Id: lonsequence.pm,v 1.47 2017/09/03 18:52:23 raeburn Exp $
+# $Id: lonsequence.pm,v 1.48.2.4 2021/12/14 21:38:14 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -245,32 +245,41 @@ sub handler {
                }
            }
 
+           &Apache::loncommon::content_type($r,'text/html');
+           $r->send_http_header;
+
+           my $mapurl = &Apache::lonnet::declutter($requrl);
+           my $maptitle = &Apache::lonnet::gettitle($mapurl);
+           my @crumbs = ({text => $maptitle, no_mt => 1});
+           my $args = {'bread_crumbs' => \@crumbs,
+                       'bread_crumbs_nomenu' => 1};
+
            # Create the nav map
            my $navmap = Apache::lonnavmaps::navmap->new();
 
            if (ref($navmap)) {
                # renderer call
                if (&Apache::lonnet::is_on_map($requrl)) {
-                   my $mapurl = &Apache::lonnet::declutter($requrl);
-                   my @crumbs = ({text  => $crstype.' Contents',
-                                  href  => "javascript:gopost('/adm/navmaps','')"});
+                   @crumbs = ({text  => $crstype.' Contents',
+                               href  => "javascript:gopost('/adm/navmaps','')"});
                    my $res = $navmap->getResourceByUrl($mapurl);
                    if (ref($res)) {
-                       my ($parent) = &Apache::lonnet::decode_symb($res->symb());
-                       if ($parent ne $env{'course.'.$env{'request.course.id'}.'.url'}) {
-                           my @mapcrumbs = $navmap->recursed_crumbs($parent);
-                           if (@mapcrumbs) {
-                               push(@crumbs,@mapcrumbs);
+                       my $symb = $res->symb();
+                       if ($symb) {
+                           my ($parent) = &Apache::lonnet::decode_symb($res->symb());
+                           if ($parent ne $env{'course.'.$env{'request.course.id'}.'.url'}) {
+                               my @mapcrumbs = $navmap->recursed_crumbs($parent);
+                               if (@mapcrumbs) {
+                                   push(@crumbs,@mapcrumbs);
+                               }
                            }
+                           $env{'request.symb'} = $symb;
                        }
                    }
-                   my $maptitle = &Apache::lonnet::gettitle($mapurl);
                    push(@crumbs,{text => $maptitle, no_mt => 1});
-                   my $args = {'bread_crumbs' => \@crumbs,
-                               'bread_crumbs_nomenu' => 1};
-                   &Apache::loncommon::content_type($r,'text/html');
-                   $r->send_http_header;
-
+                   $args = {'bread_crumbs' => \@crumbs,
+                            'bread_crumbs_nomenu' => 1,
+                            'no_auto_mt_title' => 1};
                    $r->print(&Apache::loncommon::start_page($maptitle,undef,$args));
 
                    my $renderArgs = { 'cols'                    => [0,1,2,3],
@@ -290,14 +299,27 @@ sub handler {
 
                    # If no resources were found let the user know.
                    if ($renderArgs->{'counter'} == 0) {
-                       $r->print("<p><span class=\"LC_info\">".
-                                 &mt("This folder is empty.")."</span></p>");
+                       $r->print('<p class="LC_info">'.
+                                 &mt('No items found in folder').
+                                 '</p>');
                    }
                    $r->print(&Apache::loncommon::end_page());
-                   $r->rflush();
-                   return OK;
+               } else {
+                   $r->print(&Apache::loncommon::start_page($maptitle,undef,$args).
+                             '<p class="LC_info">'.
+                             &mt('Folder no longer appears to be a part of the course').
+                             '</p>'.
+                             &Apache::loncommon::end_page());
                }
+           } else {
+               $r->print(&Apache::loncommon::start_page($maptitle,undef,$args).
+                         '<p class="LC_warning">'.
+                         &mt('Error: could not determine contents of folder').
+                         '</p>'.
+                         &Apache::loncommon::end_page());
            }
+           $r->rflush();
+           return OK;
        }
    }
 
@@ -383,10 +405,14 @@ sub handler {
       if ($is_encrypted) {
           $showdisurl = &Apache::lonenc::encrypted($disurl);
       }
-      &Apache::lonnet::symblist($requrl,$disurl => [$disurl,$dismapid],
-				'last_known' => [$disurl,$dismapid]); 
+      if ($disurl =~ m{^/adm/navmaps(\?|$)}) {
+          &Apache::lonnet::symblist($requrl,$disurl => [$disurl,$dismapid]);
+      } else {
+          &Apache::lonnet::symblist($requrl,$disurl => [$disurl,$dismapid],
+                                    'last_known' => [$disurl,$dismapid]);
+      }
       &Apache::loncommon::content_type($r,'text/html');
-      $r->header_out(Location => &Apache::lonnet::absolute_url($ENV{'SERVER_NAME'}).
+      $r->header_out(Location => &Apache::lonnet::absolute_url().
                                  $showdisurl);
       return REDIRECT;
    } else {