Hi, I'm a Silverstripe beginner and ran into a few issues. I want to be able to edit a has_one relation DataObject while editing the 'parent' (in my case an event). Since SS doesn't automatically provide a GridField or similar editing capabilities for this relation (like for many_many) I wanted to do this:

1) Create a new tab named 'Organiser' under Events that shows a GridField with all available organisers if NO link has been set to an organiser, yet. I installed the GridfieldrelationHandler extension that allows me to set the link within the GridField.

2) If a link to an organiser is already set, I want to show the GridField with a slightly config. Display only one entry with the linked record and replace the DELETE action in the GridField with an UNLINK action, because it's too easy to delete a record accidentally.

So far I ran into 2 issues:
A) The replaced DELETE action, now an UNLINK action, still deletes records from the Organisers table - even though it looks like the unlink button! Does that not work on has_one relations?

B) When I link or unlink (at the moment still delete) an organiser from an Event, the GridField does not get reloaded, hence my if/else condition doesn't work for different GridField configs in this situation. It works if I do a page reload but I suspect I need to add some kind of reload/refresh action after Silverstripe added or removed a link?

class Events extends DataObject {   
    private static $db = array (
    	'Name' => 'Varchar(100)',
    	'Date' => 'Date',
    	'ShortDesc' => 'Varchar(255)'
    );

    public static $has_one = array(
        'Organiser'    => 'Organisers'
    )

    public function getCMSfields() {
        $fields = parent::getCMSFields();

        // If an organiser is already linked to the event, use Gridfield config that only shows 1 entry with the linked organiser; add remove link action
    	if($this->Organiser()->exists()) {
			$organiserGridFieldConfig=GridFieldConfig_RecordEditor::create(1);
			$organiserGridFieldConfig->addComponent(new GridFieldHasOneRelationHandler($this, 'Organiser'));	// Using Arillo/GridfieldrelationHandler extension
			$organiserGridFieldConfig->removeComponentsByType('GridFieldDeleteAction');   						// remove default DELETE record action
			$organiserGridFieldConfig->addComponent(new GridFieldDeleteAction(true));     						// add remove link action

			$fields->addFieldToTab('Root.Organiser', $organiserGridField = new GridField('Organiser', 'Organiser', Organisers::get()->filter(array('ID'=> $this->OrganiserID)), $organiserGridFieldConfig));
        }
        // If no Organiser is linked to the Event, show all available organisers in GridField and have a different GridField config
        else {
            $organiserGridFieldConfig = GridFieldConfig_RecordEditor::create(10);
            $organiserGridFieldConfig->addComponent(new GridFieldHasOneRelationHandler($this, 'Organiser'));
            
            $fields->addFieldToTab('Root.Organiser', $organiserGridField = new GridField('Organiser', 'Organiser', Organisers::get(), $organiserGridFieldConfig));
        }

        return $fields;
    }
}


class Organisers extends DataObject {
    private static $db = array (
        'Name'          =>  'Varchar(30)',
        'City'          =>  'Varchar(30)',
        'Address'       =>  'Varchar(40)',
        'Postcode'      =>  'Varchar(10)',
        'Phone'         =>  'Varchar(20)'
    );

    public static $has_many = array(
        'Events' => 'Event'
    );
}