dataobjects.md

Using DataObjects with Fluent

CMS Fields

With each of the possible extensions that come with Fluent, it's necessary to configure your DataObjects to correctly delegate your $fields to extensions. A different approach may be needed for each DataObject, depending on how it generates it's fields.

In all cases, it is necessary to ensure that the updateCMSFields extension method is called once (and only once) on each FieldList object.

Default field scaffolder

If using a default field scaffolder (such as SiteTree::getCMSFields or DataObject::getCMSFields) it is necessary to know that these methods both, by default, will call the extend('updateCMSFields', $fields) extension before returning.

If you wish to add any translated form fields to the result of this call, then you should use beforeUpdateCMSFields

class MyPage extends SiteTree
{
	public function getCMSFields()
    {
		// Adding the Description field early will allow FluentField to decorate this with the appropriate
		// CSS classes.
		$this->beforeUpdateCMSFields(function($fields) {
			$fields->addFieldToTab('Root.Main', new TextField('Description'));
		});

		// The result of this call will have had beforeUpdateCMSFields then updateCMSFields called on it
		$fields = parent::getCMSFields();
		$fields->removeByName('Content', true);
		return $fields;
	}
}

Explicit field generation

If explicitly generating your FieldList, simply make sure to call the appropriate extension hook prior to returning.

class MyObject extends DataObject
{
	public function getCMSFields()
    {
		// Note the absence of any parent::getCMSFields
		$fields = new FieldList(
			new TextField('Title', 'Title', null, 255),
			new TextareaField('Description')
		);

		// This line is necessary, and only AFTER you have added your fields
		$this->extend('updateCMSFields', $fields);
		return $fields;
	}
}

Extensions

As mentioned in the CMS Fields heading, it is necessary to ensure that the updateCMSFields extension method is called once (and only once) on each FieldList object. Fields added by other extensions will not have the necessary decorations applied to it by the FluentExtension, unless it happens to be applied before FluentExtension. Since extension order cannot be guaranteed, this poses a problem.

You can circumvent this issue by extending FluentExtension from your custom extension and then calling parent::updateCMSFields($fields) at the end of your method. This way it is actually one call to updateCMSFields using inheritance rather than two different extensions:

use TractorCow\Fluent\Extension\FluentExtension;

class PlayerExtension extends FluentExtension
{
    public function updateCMSFields(FieldList $fields)
    {
        $fields->removeByName('SomeIrrelevantField');
        parent::updateCMSFields($fields);
    }
}

Versioned extension

Important: If you're applying the FluentVersionedExtension to a versioned DataObject, you will need to ensure that it is applied after the Versioned extension. You can control this with an after: '#versionedfiles' rule in your YAML title block. An example configuration block might look like this:

---
Name: mysitefluent
After: '#versionedfiles'
---
SilverStripe\Assets\File:
  extensions:
    - TractorCow\Fluent\Extension\FluentVersionedExtension
  translate:
    - Title