private function processSpineElement(SimpleXMLElement $xml, Spine $spine, Manifest $manifest, Navigation $navigation)
{
$position = 1;
foreach ($xml->itemref as $child) {
$id = (string) $child['idref'];
$manifestItem = $manifest->get($id);
if (!($linear = $child['linear'])) {
$linear = 'yes';
}
$item = new SpineItem();
$item->id = $id;
$item->type = $manifestItem->type;
$item->href = $manifestItem->href;
$item->order = $position;
$item->linear = $linear;
$this->addContentGetter($item);
$spine->add($item);
$position++;
}
$ncxId = $xml['toc'] ? (string) $xml['toc'] : 'ncx';
if ($manifest->has($ncxId)) {
$navigation->src = $manifest->get($ncxId);
}
}
