MDL-59612 core: added previous and next links to activities

Part of MDL-59313.

course/classes/output/activity_navigation.php

+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * File containing the class activity navigation renderable.
+ *
+ * @package    core_course
+ * @copyright  2017 Mark Nelson <markn@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core_course\output;
+
+defined('MOODLE_INTERNAL') || die();
+
+use renderable;
+use templatable;
+
+/**
+ * The class activity navigation renderable.
+ *
+ * @package    core_course
+ * @copyright  2017 Mark Nelson <markn@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class activity_navigation implements renderable, templatable {
+
+    /**
+     * @var string The html for the prev link
+     */
+    public $prevlink = '';
+
+    /**
+     * @var string The html for the next link
+     */
+    public $nextlink = '';
+
+    /**
+     * Constructor.
+     *
+     * @param \cm_info|null $prevmod The previous module to display, null if none.
+     * @param \cm_info|null $nextmod The previous module to display, null if none.
+     */
+    public function __construct($prevmod, $nextmod) {
+        global $OUTPUT;
+
+        // Check if there is a previous module to display.
+        if ($prevmod) {
+            $linkname = $prevmod->name;
+            if (!$prevmod->visible) {
+                $linkname .= ' ' . get_string('hiddenwithbrackets');
+            }
+
+            $link = new \action_link($prevmod->url, $OUTPUT->larrow() . ' ' . $linkname);
+            $this->prevlink = $OUTPUT->render($link);
+        }
+
+        // Check if there is a next module to display.
+        if ($nextmod) {
+            $linkname = $nextmod->name;
+            if (!$nextmod->visible) {
+                $linkname .= ' ' . get_string('hiddenwithbrackets');
+            }
+
+            $link = new \action_link($nextmod->url, $linkname . ' ' . $OUTPUT->rarrow());
+            $this->nextlink = $OUTPUT->render($link);
+        }
+    }
+
+    /**
+     * Export this data so it can be used as the context for a mustache template.
+     *
+     * @param \renderer_base $output Renderer base.
+     * @return \stdClass
+     */
+    public function export_for_template(\renderer_base $output) {
+        $data = new \stdClass();
+        $data->prevlink = $this->prevlink;
+        $data->nextlink = $this->nextlink;
+
+        return $data;
+    }
+}

course/renderer.php

@@ -2100,6 +2100,19 @@ class core_course_renderer extends plugin_renderer_base {
                 set_attributes(array('class' => 'frontpage-category-names'));
         return $this->coursecat_tree($chelper, coursecat::get(0));
     }
+
+    /**
+     * Renders the activity navigation.
+     *
+     * Defer to template.
+     *
+     * @param \core_course\output\activity_navigation $page
+     * @return string html for the page
+     */
+    public function render_activity_navigation(\core_course\output\activity_navigation $page) {
+        $data = $page->export_for_template($this->output);
+        return $this->output->render_from_template('core_course/activity_navigation', $data);
+    }
 }
 
 /**

course/templates/activity_navigation.mustache

+{{!
+    This file is part of Moodle - http://moodle.org/
+
+    Moodle is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Moodle is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+}}
+{{!
+    @template core_course/activity_navigation
+
+    Displays the activity navigation
+
+    Context variables required for this template:
+    * prevlink - The link to the previous module the user can see
+    * nextlink - The link to the next module the user can see
+
+    Example context (json):
+    {
+        "prevlink": "<a href='#'>The origins of Moodle</a>",
+        "nextlink": "<a href='#'>Moodlers - are they contagious?</a>"
+    }
+}}
+<div>
+{{< core/columns-1to1to1}}
+    {{$column1}}
+        <div class="pull-left">
+            {{{prevlink}}}
+        </div>
+    {{/column1}}
+    {{$column3}}
+        <div class="pull-right">
+            {{{nextlink}}}
+        </div>
+    {{/column3}}
+{{/ core/columns-1to1to1}}
+</div>

lang/en/moodle.php

@@ -931,6 +931,7 @@ $string['hiddensections'] = 'Hidden sections';
 $string['hiddensections_help'] = 'This setting determines whether hidden sections are displayed to students in collapsed form (perhaps for a course in weekly format to indicate holidays) or are completely hidden.';
 $string['hiddensectionscollapsed'] = 'Hidden sections are shown in collapsed form';
 $string['hiddensectionsinvisible'] = 'Hidden sections are completely invisible';
+$string['hiddenwithbrackets'] = '(hidden)';
 $string['hide'] = 'Hide';
 $string['hideadvancedsettings'] = 'Hide advanced settings';
 $string['hidechartdata'] = 'Hide chart data';

lib/outputrenderers.php

@@ -813,6 +813,68 @@ class core_renderer extends renderer_base {
         return '<div role="main">'.$this->unique_main_content_token.'</div>';
     }
 
+    /**
+     * Returns standard navigation between activities in a course.
+     *
+     * @return string the navigation HTML.
+     */
+    public function activity_navigation() {
+        // First we should check if we want to add navigation.
+        $context = $this->page->context;
+        if ($this->page->pagelayout !== 'incourse' || $context->contextlevel != CONTEXT_MODULE) {
+            return '';
+        }
+
+        // If the activity is in stealth mode, show no links.
+        if ($this->page->cm->is_stealth()) {
+            return '';
+        }
+
+        // Get a list of all the activities in the course.
+        $course = $this->page->cm->get_course();
+        $modules = get_fast_modinfo($course->id)->get_cms();
+
+        // Put the modules into an array in order by the position they are shown in the course.
+        $mods = [];
+        foreach ($modules as $module) {
+            // Only add activities the user can access, aren't in stealth mode and have a url (eg. mod_label does not).
+            if (!$module->uservisible || $module->is_stealth() || empty($module->url)) {
+                continue;
+            }
+            $mods[$module->id] = $module;
+        }
+
+        $nummods = count($mods);
+
+        // If there is only one mod then do nothing.
+        if ($nummods == 1) {
+            return '';
+        }
+
+        // Get an array of just the course module ids used to get the cmid value based on their position in the course.
+        $modids = array_keys($mods);
+
+        // Get the position in the array of the course module we are viewing.
+        $position = array_search($this->page->cm->id, $modids);
+
+        $prevmod = null;
+        $nextmod = null;
+
+        // Check if we have a previous mod to show.
+        if ($position > 0) {
+            $prevmod = $mods[$modids[$position - 1]];
+        }
+
+        // Check if we have a next mod to show.
+        if ($position < ($nummods - 1)) {
+            $nextmod = $mods[$modids[$position + 1]];
+        }
+
+        $activitynav = new \core_course\output\activity_navigation($prevmod, $nextmod);
+        $renderer = $this->page->get_renderer('core', 'course');
+        return $renderer->render($activitynav);
+    }
+
     /**
      * The standard tags (typically script tags that are not needed earlier) that
      * should be output after everything else. Designed to be called in theme layout.php files.

theme/boost/templates/columns2.mustache

@@ -82,6 +82,7 @@
                     {{/hasregionmainsettingsmenu}}
                     {{{ output.course_content_header }}}
                     {{{ output.main_content }}}
+                    {{{ output.activity_navigation }}}
                     {{{ output.course_content_footer }}}
                     </div>
                 </section>

theme/bootstrapbase/layout/columns3.php

@@ -69,6 +69,7 @@ echo $OUTPUT->doctype() ?>
                     <?php
                     echo $OUTPUT->course_content_header();
                     echo $OUTPUT->main_content();
+                    echo $OUTPUT->activity_navigation();
                     echo $OUTPUT->course_content_footer();
                     ?>
                 </section>

theme/clean/layout/columns3.php

@@ -76,6 +76,7 @@ echo $OUTPUT->doctype() ?>
                     <?php
                     echo $OUTPUT->course_content_header();
                     echo $OUTPUT->main_content();
+                    echo $OUTPUT->activity_navigation();
                     echo $OUTPUT->course_content_footer();
                     ?>
                 </section>

theme/upgrade.txt

@@ -9,6 +9,8 @@ information provided here is intended especially for theme designer.
   the first one was renamed to loginform.mustache - see MDL-58970.
 * The Boost flat navigation nodes now have several data-attributes which let plugin developers
   access properties from the underlying navigation nodes in the browser - see MDL-59425.
+* Navigation between activities via a previous and next link was added to Boost, Clean and Bootstrapbase. This
+  is made possible by a new function core_renderer->activity_navigation().
 
 === 3.3 ===