@amir.mostofi
Try
...
public function getCMSFields()
{
$f = parent::getCMSFields();
$f->addFieldToTab("Root.Content.HeaderImage", new ImageField('HeaderImage'));
$manager = new FileDataObjectManager(
$this, // Controller
'ImageAttachments', // Source name
'ImageAttachment', // Source class
'Attachment', // File name on DataObject
array(
'Name' => 'Name',
'URL' => 'URL'
), // Headings
'getCMSFields_forPopup', // Detail fields (function name or FieldSet object)
"PageID = {$this->ID}" // Filter clause
// Sort clause
// Join clause
);
$manager->setParentClass('Page');
...