Returns the highest last-modified value of all assets in the current collection.
integer|null A UNIX timestamp
Overrides AssetInterface::getLastModified
public function getLastModified() {
if (!count($this->assets)) {
return;
}
$mtime = 0;
foreach ($this as $asset) {
$assetMtime = $asset
->getLastModified();
if ($assetMtime > $mtime) {
$mtime = $assetMtime;
}
}
return $mtime;
}