TUTORIAL : How to display Previous and Next Links using getResources

Home/            # Home page // Not really needed in our tutorial
|
|-- Book/                   # Container - Book's summary page. ID: 927 (Yours could be different). 
|   |-- chapter-1.html      # Pagetitle: My Awesome Book. Template: Book_chapters (44)
|   |-- chapter-2.html      # Pagetitle: My Awesome Book. Template: Book_chapters (44)
|   |-- chapter-3.html      # Idem
|   |-- chapter-4.html      # etc.
|   |-- chapter-5.html      
|   ...
|   |-- chapter-12.html

[[getResources@FooterNav? &property=`value`]]

 depth=`0`
 level=`1`
 maxLevel=`2`
 sortby=`menuindex`
 sortdir=`ASC`
 tpl=`myRowTpl`// Used for the next link
 tplFirst=`myFirstRowTpl` // Used for the previous link
 tplWrapper=`myWrapperTpl`
 showHidden=`Yes` // My resources are hidden from the tree. Yours may not be, so this is optional.

//Styled with Bootstrap V.3.1.1
<div class="btn-group pull-right">
 <a href="[[~[[+id]]]]" class="btn btn-default" title="[[+pagetitle]] Chapter [[+tv.Chapter]]" rel="next">[[+pagetitle]] Chapter [[+tv.Chapter]] →</a> 
[[[[+level:lt=`[[+maxLevel]]`:then=`getResources@FooterNav? &parents=`[[+id]]` &level=`[[+level:add]]``:else=`-`]]]]          
</div>

//Styled with Bootstrap V.3.1.1
<div class="btn-group pull-left">
 <a href="[[~[[+id]]]]" class="btn btn-default bbl-toolbar-btn" title="[[+pagetitle]] Chapter [[+tv.Chapter]]" rel="prev">← [[+pagetitle]] Chapter [[+tv.Chapter]]</a>
[[[[+level:lt=`[[+maxLevel]]`:then=`getResources@FooterNav? &parents=`[[+id]]` &level=`[[+level:add]]``:else=`-`]]]]          
</div>

//You can add some HTML if you like. 
[[+output]]

/**
 * getPreviousChap
 *
 * DESCRIPTION
 *
 * Helper Snippet that subtracts &y from the supplied number &x 
 *
 * PROPERTIES:
 *
 * &x integer required. Default: 1
 *
 * USAGE:
 *
 * [[!getPreviousChap? &x=`10` &y=`1`]]
 *
 */
$x = (int) $modx->getOption('x', $scriptProperties, 1);
$y = (int) $modx->getOption('y', $scriptProperties);

return $x - $y;

<!-- Footer nav-->    
//Styled with Bootstrap V.3.1.1
<div class="panel panel-default">
  <div class="panel-body">
    <!-- Previous link -->
    [[*Chapter:gt=`1`:then=`[[getResources@FooterNav? &parents=`927` &limit=`1` &includeTVs=`1` &processTVs=`1` &offset=`[[getPreviousChap? &x=`[[*Chapter]]` &y=`2`]]` &where=`{"template:=":44, "pagetitle:=":"[[*pagetitle]]"}`]]`]]
    <!--/. Previous link -->

    <!-- Next link -->
    [[getResources@FooterNav? &parents=`927` &limit=`1` &includeTVs=`1` &processTVs=`1` &offset=`[[*Chapter]]` &where=`{"template:=":44, "pagetitle:=":"[[*pagetitle]]"}`]]
    <!--/. Next link -->
  </div>
</div>
<!--/. Footer nav-->

<?php
/*
 *@snippet NextChild
 *
 *Helper snippet that displays previous and next links 
 *Requires getResources
 *
 * Basic Usage: -- See optimized usage in the notes below
 *
 *	[[!NextChild? &x=`[[*myOffsetTV]]`]] => will display the next page link
 *	[[!NextChild? &navdir=`left` &tpl=`tplPrevChild` &x=`[[*myOffsetTV]]`]] => will display the previous page link
 */

// set defaults
$output    = $modx->getOption('default', $scriptProperties, '');
$parents   = $modx->getOption('parents', $scriptProperties, 927); // Document ID
$template  = $modx->getOption('template', $scriptProperties, 44); // Template ID
$tpl       = $modx->getOption('tpl', $scriptProperties, 'tplNextChild');
//id of the document from which to retrieve the pagetitle. 
$id        = $modx->getOption('id', $scriptProperties, $modx->resource->get('id'));
$page      = $modx->getObject('modResource', $id);
$pagetitle = $page->get('pagetitle');
//Navigation direction: left or right. Defaults to right => next page link
$navdir    = $modx->getOption('navdir', $scriptProperties, 'right');
// Utility property used to determine the offset value. See line 30
$x         = (int) $modx->getOption('x', $scriptProperties, 1);

//Create the offset value for getResources
//This is technically how the previous 
//and next links are generated
if ($navdir == 'left' && $x <= 1) {
    
    $offset = 0;
    
} elseif ($navdir == 'left' && $x > 1) {
    
    $offset = $x - 2;
    
} else {
    $offset = $x;
}

//getResources options
$where = array(
    'template:=' => 44,
    'pagetitle:LIKE' => '%' . $pagetitle . '%'
);

$params = array(
    'parents' => $parents,
    'depth' => 0,
    'showHidden' => 1,
    'where' => $modx->toJson($where),
    'limit' => 1,
    'offset' => $offset,
    'level' => 1, //Custom property
    'max_level' => 2, //Custom property
    'includeTVs' => 1,
    //For perfomarce reasons, let's only get the TVs we need
    'includeTVList' => 'Chapter',
    'sortby' => 'menuindex',
    'sortdir' => 'ASC',
    'sortdirTV' => 'ASC',
    'tpl' => $tpl,
    'tplWrapper' => $tplWrapper
);

//Run getResources to grab our target pages
$output = $modx->runSnippet('getResources', $params);

// Return results 
return $output;

[[[[*Chapter:lt=`[[+total]]`:then=`!NextChild? &x=`[[*Chapter]]``]]]]

[[[[*Chapter:gt=`1`:then=`!NextChild? &navdir=`left` &tpl=`tplPrevChild` &x=`[[*Chapter]]``]]]]

<a href="[[~[[+id]]]]" title="[[+pagetitle]] Chapter [[+tv.Chapter]]" rel="next">[[+pagetitle]] Chapter [[+tv.Chapter]] →</a>

<a href="[[~[[+id]]]]" title="[[+pagetitle]] Chapter [[+tv.Chapter]]" rel="previous">← [[+pagetitle]] Chapter [[+tv.Chapter]]</a>