PagingFeature.inc.php

<?php
 
import('lib.pkp.classes.controllers.grid.feature.GeneralPagingFeature');
 
class PagingFeature extends GeneralPagingFeature {
 
   function __construct($id = 'paging') {
      parent::__construct($id);
   }
 
 
   //
   // Extended methods from GridFeature.
   //
   function getJSClass() {
      return '$.pkp.classes.features.PagingFeature';
   }
 
 
   function fetchUIElements($request, $grid) {
      $options = $this->getOptions();
      $templateMgr = TemplateManager::getManager($request);
      $templateMgr->assign(array(
         'iterator' => $this->getItemIterator(),
         'currentItemsPerPage' => $options['currentItemsPerPage'],
         'grid' => $grid,
      ));
      return array('pagingMarkup' => $templateMgr->fetch('controllers/grid/feature/gridPaging.tpl'));
   }
 
 
   //
   // Hooks implementation.
   //
   function fetchRow($args) {
      $request = $args['request'];
      $grid = $args['grid'];
      $row = $args['row'];
      $jsonMessage = $args['jsonMessage'];
      $pagingAttributes = array();
 
      if (is_null($row)) {
         $gridData = $grid->getGridDataElements($request);
         $iterator = $this->getItemIterator();
         $rangeInfo = $grid->getGridRangeInfo($request, $grid->getId());
 
         // Check if row was really deleted or if the requested row is
         // just not inside the requested range.
         $deleted = true;
         $topLimitRowId = (int) $request->getUserVar('topLimitRowId');
         $bottomLimitRowId = (int) $request->getUserVar('bottomLimitRowId');
 
         reset($gridData);
         $firstDataId = key($gridData);
         next($gridData);
         $secondDataId = key($gridData);
         end($gridData);
         $lastDataId = key($gridData);
 
         if ($secondDataId == $topLimitRowId) {
            $deleted = false;
            // Case 1.
            // Row was added but it's on previous pages, so the first
            // item of the grid was moved to the second place by the added
            // row. Render the first one that's currently not visible yet in
            // grid.
            $args = array('rowId' => $firstDataId);
            $row = $grid->getRequestedRow($request, $args);
            $pagingAttributes['newTopRow'] = $grid->renderRow($request, $row);
         }
 
         if ($firstDataId == $topLimitRowId && $lastDataId == $bottomLimitRowId) {
            $deleted = false;
         }
 
         if ($deleted) {
            if ((empty($gridData) ||
               // When DAOResultFactory, it seems that if no items were found for the current
               // range information, the last page is fetched, which give us grid data even if
               // the current page is empty. So we check for iterator and rangeInfo current pages.
               $iterator->getPage() != $rangeInfo->getPage())
               && $iterator->getPageCount() >= 1) {
               // Case 3.
               $pagingAttributes['loadLastPage'] = true;
            } else {
               if (count($gridData) >= $rangeInfo->getCount()) {
                  // Case 2.
                  // Get the last data element id of the current page.
                  end($gridData);
                  $firstRowId = key($gridData);
 
                  // Get the row and render it.
                  $args = array('rowId' => $firstRowId);
                  $row = $grid->getRequestedRow($request, $args);
                  $pagingAttributes['deletedRowReplacement'] = $grid->renderRow($request, $row);
               }
            }
         }
      }
 
      // Render the paging options, including updated markup.
      $this->setOptions($request, $grid);
      $pagingAttributes['pagingInfo'] = $this->getOptions();
 
      // Add paging attributes to json so grid can update UI.
      $additionalAttributes = $jsonMessage->getAdditionalAttributes();
      $jsonMessage->setAdditionalAttributes(array_merge(
         $pagingAttributes,
         $additionalAttributes)
      );
   }
}