public function addLocator(LocatorInterface $locator, $id = null) {
		if ($id === null) {
			$this->_locators[] = $locator;
		} else {
			$this->_locators[$id] = $locator;
		}
		
		return $this;
	}
public function addLocator(LocatorInterface $locator, $id = null) {
		if ($id === null) {
			$this->_locators[] = $locator;
		} else {
			$this->_locators[$id] = $locator;
		}
		
		return $this;
	}
public function addLocator ( LocatorInterface $ locator , $ id = null ) { if ( $ id === null ) { $ this -> _locators [ ] = $ locator ; } else { $ this -> _locators [ $ id ] = $ locator ; } return $ this ; }
Add fallback locator

@param  LocatorInterface $locator Locator instance
@param  string           $id      Locator unique ID
@return Container
Add fallback locator