Hi all,

I have created a ProductPage Template that I want to be able to use in a site.

Code example below;

	class ProductPage extends Page {
	
		public static $db = array(
			'Price' => 'Currency',
			'SalePrice' => 'Currency',
			'ProductCode' => 'Text'
		);

		public static $has_many = array(
			'ProductImages' => 'ProductImage'
		);
		public static $has_one = array(
			'ProductPage' => 'Homepage'
			);

		function getCMSFields() {
			$fields = parent::getCMSFields();
	
			$fields->addFieldToTab('Root.Content.Main', new TextField('Price', 'Price'), 'Content');
			$fields->addFieldToTab('Root.Content.Main', new TextField('SalePrice', 'SalePrice'), 'Content');
			$fields->addFieldToTab('Root.Content.Main', new TextField('ProductCode', 'ProductCode'), 'Content');

			$tablefield = new DataObjectManager(
							$this,
							'ProductImages',
							'ProductImage',
							array( 'Thumbnail' => 'Image', 'Title' => 'Title'),
							'getCMSFields_forPopup'
							);

			$tablefield->setPageSize(100);
			$tablefield->setAddTitle( 'A Image' );

			$fields->addFieldToTab( 'Root.Content.ProductImages', $tablefield );

			return $fields;
		}
	
	}

Now I would like to gather all these products and give the user the oppurtunity to display them on the homepage in a list. I had a thought, I can use HasManyDataObjectManager. So I have written the HomePage like this;

	class HomePage extends Page {
	
		public static $db = array(
		);
	
		public static $has_one = array(
		);
		public static $has_many = array(
			'Specials' => 'ProductPage'
		);
	
		function getCMSFields() {
			$fields = parent::getCMSFields();

			$manager = new HasManyDataObjectManager(
							$this,
							'Specials',
							'ProductPage',
							array('Title' => 'Title'),
							'getCMSFields_forPopup'
							);
			$perms = array();//Don't want to be able to Remove, Delete, View, Add from here.
			$manager->setPermissions($perms);

			$fields->addFieldToTab( 'Root.Content.Specials', $manager );

			return $fields;
		}
	}

Now it all works sweet with one small exception, I can't select the item in the admin. I can see the checkbox but it is disabled.

The problem doesn't appear to be DataObjectManager Specific as I removed it and went back to the standard method with the same result.

Any help would be greatly appreciated.

Because you're using a HasManyDOM, remember that the reciprocal of a has_many is a has_one, which means that if those records are already related to a different object, they're not going to be selectable. You may want ManyManyDOM, or, if you're not doing any add/delete/edit, use a CheckboxSetField or, my favorite, MultiSelectField (separate module).