Hi all ok I'm playing around with my first form. My question is --

in the example below, headers_sent(...) resolves to true so it does this almighty heavy weight 'redirecting to...'. How do I avoid this so that Director::redirect() calls header(...) instead.

I looked at PageComments and it does the same thing as below but doesn't do the heavyweight redirect; what have I done wrong that means that a simple form submission (could it get any simpler? A single action) sends header information.

thanks in advance!
J

code below
---

   /** an opinion is a gesture of thought by user -- marking as favourite or comment or whatever. */
   function OpinionForm() {
      $loggedInMember = Member::currentUser();
      
      // user is authenticated, so return elements in the form.
      // if the user isn't authenticated, we will require them to when they do something.
      if( $loggedInMember ) {
         $artwork = $this->data();
      
         // we have a member so find whether this artwork was marked as favourite and highlight as appropriate.
         // returns a ComponentSet.
         $members = $artwork->getManyManyComponents('MemberFavourites');
         if( $members ) {
            $memberMap = $members->map();
            
            // this is not marked as a favourite, so give them the option to do this
            if( !$memberMap[$loggedInMember->ID]) {
               $faveAction = new ImageFormAction('doMarkAsFavourite', 'Mark Artwork as favourite', 'mysite/images/fave_unselected.gif', 'mysite/images/fave_selected.gif' );         
            
            // ALREADY MARKED. Present option to unmark.
            } else {
               $faveAction = new ImageFormAction('doUnmarkFavourite', 'Remove from favourites list', 'mysite/images/fave_selected.gif', 'mysite/images/fave_unselected.gif' );                        
            }
         }
         
         $fields = new FieldSet();
         $actions = new FieldSet( $faveAction );
         return new Form( $this, 'OpinionForm', $fields, $actions );
         
         // TODO -- change icon based on state of favourite
      }
   }
   
   /** user chose this to be a favourite against currently authenticated member. */
   function doMarkAsFavourite() {
      $loggedInMember = Member::currentUser();
      
      if( $loggedInMember ) {
         $artwork = $this->data();
         $members = $artwork->getManyManyComponents('MemberFavourites');
         $members->add( $loggedInMember );
         Director::redirectBack();
      }
   }