public function scaffoldFormField($title = null, $params = null)
{
if (empty($this->object)) {
return null;
}
$relationName = substr($this->name, 0, -2);
$hasOneClass = $this->object->hasOneComponent($relationName);
if (empty($hasOneClass)) {
return null;
}
$hasOneSingleton = singleton($hasOneClass);
if ($hasOneSingleton instanceof File) {
$field = new UploadField($relationName, $title);
if ($hasOneSingleton instanceof Image) {
$field->setAllowedFileCategories('image/supported');
}
return $field;
}
// Build selector / numeric field
$titleField = $hasOneSingleton->hasField('Title') ? "Title" : "Name";
$list = DataList::create($hasOneClass);
// Don't scaffold a dropdown for large tables, as making the list concrete
// might exceed the available PHP memory in creating too many DataObject instances
if ($list->count() < 100) {
$field = new DropdownField($this->name, $title, $list->map('ID', $titleField));
$field->setEmptyString(' ');
} else {
$field = new NumericField($this->name, $title);
}
return $field;
}