Looping through a dataobject with a $has_many relationship? - silverstripe

Question

I have a $has_many relation on my DashboardPage to my PastEvent dataobject. In my DashboardPage.ss template I want to be able to loop through all the PastEvents. I believe because of the $has_many relationship I should be able to do the following on the DashboardPage.ss template:
DashboardPage.ss
<% loop $PastEvents %>
<div>
<div>$EventName</div>
<div>$ClassType</div>
etc...
</div>
<% end_loop %>
However nothing is showing. What am I missing?
DashboardPage.php
<?php
class DashboardPage extends Page implements TemplateGlobalProvider {
private static $db = array(
'Testing' => 'Varchar(255)'
);
private static $has_many = array(
'PastEvents' => 'PastEvent'
);
public function getCMSFields() {
$fields = parent::getCMSFields();
$fields->removeByName('Content');
return $fields;
}
public static function get_template_global_variables() {
return array('DashboardLink' => 'getDashboardLink');
}
public static function getDashboardLink($action='') {
$page = DashboardPage::get()->first();
return $page ? $page->Link($action) : '';
}
}
class DashboardPage_Controller extends Page_Controller {
private static $allowed_actions = array(
'show'
);
public function init() {
parent::init();
Requirements::css('themes/' . SSViewer::current_theme() . '/owl-carousel/owl.carousel.css');
Requirements::css('themes/' . SSViewer::current_theme() . '/owl-carousel/owl.theme.css');
Requirements::css('themes/' . SSViewer::current_theme() . '/owl-carousel/owl.transitions.css');
}
public function show(){
dd('Coming here');
}
}
PastEvent.php
<?php
class PastEvent extends DataObject {
private static $db = array(
'EventName' => 'Varchar(255)',
'ClassType' => 'Varchar(255)',
'Instructor' => 'Varchar(255)',
'EmbedCode' => 'Text',
'EventDate' => 'Date',
'Time' => 'Time'
);
private static $has_one = array(
'BranchLocation' => 'BranchLocation',
'DashboardPage' => 'DashboardPage'
);
private static $summary_fields = array(
'EventName' => 'EventName',
'BranchLocation.Name' => 'Branch Location',
'ClassType' => 'ClassType',
'Instructor' => 'Instructor',
'EventDate' => 'Event Date',
'Time' => 'Time',
);
public function getCMSFields() {
$fields = new FieldList(
TextField::create('EventName'),
TextField::create('ClassType'),
TextField::create('Instructor'),
DropdownField::create(
'BranchLocationID',
'Branch Location',
BranchLocation::get()->map('ID', 'Name')->toArray()
),
TextareaField::create('EmbedCode'),
DateField::create('EventDate')->setConfig('showcalendar', true)->setDescription('Click inside textbox to open calender'),
TimePickerField::create('Time')
);
return $fields;
}
public function Link() {
return $this->DashboardPage()->Link('show/'.$this->ID);
}
}

Answer 1

You need to manage PastEvent on the DashboardPage
public function getCMSFields() {
...
$fields->push(GridField::create('PastEvents', 'Past Events',
$this->PastEvents(),
singleton('PastEvent')->canEdit()
? GridFieldConfig_RecordEditor::create()
: GridFieldConfig_RecordViewer::create()
));
...
}
You can add past events from another place, assuming that you created your page with '/dashboard' url.
$dashboard = SiteTree::get_by_link('dashboard');
$events = $dashboard->PastEvents();
$events->add($this->createNewEvent());
You don't need your show() action to display the DashboardPage (implicit index() action is used by default). Page actions extend page url, so your action will be called when you request /dashboard/show, that seems is your intention.
Improve your template to show that there are no events:
<% if $PastEvents.Count %>
<ul>
<% loop $PastEvents %>
<li>
$EventName
<div>$ClassType</div>
...
</li>
<% end_loop %>
</ul>
<% else %>
<p>There are no past events.</p>
<% end_if %>
Since your page provides proper link to show action
public function Link() {
return $this->DashboardPage()->Link('show/'.$this->ID);
}
Your show action might be like this
public function show($eventID = 0) {
$event = $this->PastEvents()->byID($eventID);
if (!$event) {
$this->httpError(404);
}
// render with templates/Page.ss and templates/Layout/PastEventDetails.ss
return $event->renderWith(array('PastEventDetails', 'Page'));
}