Contao: Pick and display individual events

contao_config_config.php

<?php
# contao/config/config.php

use App\ModulePickedEventlist;

$GLOBALS['FE_MOD']['events']['pickedeventlist'] = ModulePickedEventlist::class;

contao_dca_tl_module.php

<?php
# contao/dca/tl_module.php

use Contao\CoreBundle\DataContainer\PaletteManipulator;


//$GLOBALS['TL_DCA']['tl_module']['palettes']['pickedeventlist'] = '{title_legend},name,headline,type;{config_legend},cal_calendar,cal_noSpan,cal_format,cal_featured,cal_order,cal_readerModule,cal_limit,perPage,cal_ignoreDynamic,cal_hideRunning;{template_legend:hide},cal_template,customTpl;{image_legend:hide},imgSize;{protected_legend:hide},protected;{expert_legend:hide},cssID;{events_legend},pickedevents';
$GLOBALS['TL_DCA']['tl_module']['palettes']['pickedeventlist'] = $GLOBALS['TL_DCA']['tl_module']['palettes']['eventlist'];

PaletteManipulator::create()
    ->removeField('cal_calendar', 'config_legend')
    ->removeField('cal_format', 'config_legend')
    ->removeField('cal_featured', 'config_legend')
    ->removeField('cal_order', 'config_legend')
    ->removeField('cal_ignoreDynamic', 'config_legend')
    ->removeField('cal_hideRunning', 'config_legend')
    ->removeField('cal_limit', 'config_legend')
    ->addLegend('events_legend', 'title_legend', PaletteManipulator::POSITION_AFTER)
    ->addField('pickedevents', 'events_legend', PaletteManipulator::POSITION_APPEND)
    ->applyToPalette('pickedeventlist', 'tl_module')
;

$GLOBALS['TL_DCA']['tl_module']['fields']['pickedevents'] = [
    'label' => &$GLOBALS['TL_LANG']['tl_module']['pickedevents'],
    'inputType' => 'picker',
    'eval' => [
        'multiple' => true,
        'isSortable' => true,
    ],
    'sql' => [
        'type' => 'blob',
        'notnull' => false,
    ],
    'foreignKey' => 'tl_calendar_events.id',
    'relation' => [
        'type' => 'hasMany',
        'load' => 'lazy',
        'table' => 'tl_calendar_events',
    ],
];

contao_languages_de_tl_module.php

<?php
# contao/languages/de/tl_module.php

$GLOBALS['TL_LANG']['FMD']['pickedeventlist'] = [
    'Ausgewählte Events',
    'Module zur Darstellung ausgewählter Events'
];

$GLOBALS['TL_LANG']['tl_module']['events_legend'] = 'Events';

$GLOBALS['TL_LANG']['tl_module']['pickedevents'] = ['Anzuzeigende Events', 'Im Modul anzuzeigende Events auswählen und nach Bedarf sortieren.'];

src_ModulePickedEventlist.php

<?php
# src/ModulePickedEventlist.php

namespace App;

use Contao\BackendTemplate;
use Contao\CalendarEventsModel;
use Contao\ModuleEventlist;
use Contao\StringUtil;
use Contao\System;

class ModulePickedEventlist extends ModuleEventlist
{

    private array $pickedEventsIds;
    private array $pickedEventsCalendarIds;

    public function generate()
    {
        $request = System::getContainer()->get('request_stack')->getCurrentRequest();

        if ($request && System::getContainer()->get('contao.routing.scope_matcher')->isBackendRequest($request))
        {
            $objTemplate = new BackendTemplate('be_wildcard');
            $objTemplate->wildcard = '### ' . ($GLOBALS['TL_LANG']['FMD']['pickedeventlist'][0] ?? 'pickedeventlist'). ' ###';
            //$objTemplate->wildcard = '### PickedEventList ###';
            $objTemplate->title = $this->headline;
            $objTemplate->id = $this->id;
            $objTemplate->link = $this->name;
            $objTemplate->href = StringUtil::specialcharsUrl(System::getContainer()->get('router')->generate('contao_backend', array('do'=>'themes', 'table'=>'tl_module', 'act'=>'edit', 'id'=>$this->id)));

            return $objTemplate->parse();
        }

        $this->setData();

        return parent::generate();
    }

    // protected function compile()
    // {
    //     return parent::compile();
    // }

    protected function setData(): void
    {
        $this->pickedEventsIds = StringUtil::deserialize($this->pickedevents);
        foreach ($this->pickedEventsIds as $eventId) {
            $event = CalendarEventsModel::findById($eventId);
            $this->pickedEventsCalendarIds[] = $event->pid;
        }
        $this->pickedEventsCalendarIds = array_unique($this->pickedEventsCalendarIds);

        $this->cal_calendar = $this->pickedEventsCalendarIds;
        $this->cal_format = 'cal_all'; // 'Alle Events'
        $this->cal_featured = 'all_items'; // 'Alle Events anzeigen'
        $this->cal_order = 'ascending';
        $this->cal_ignoreDynamic = true; // URL-Parameter ignorieren
        $this->cal_hideRunning = false;
        $this->cal_limit = 0;

    }
}

"Of course" the module code (as above) is missing the

protected function getAllEvents($arrCalendars, $intStart, $intEnd, $blnFeatured = null)
    {
        $eventIds = StringUtil::deserialize($this->pickedevents);
        foreach ($eventIds as $eventId) {
            $event = CalendarEventsModel::findById($eventId);
            $this->addEvent($event, $event->startTime, $event->endTime, $intStart, $intEnd, $event->pid);
        }

        return $this->arrEvents;
    }

method to restrict the events to the picked ones.