Method exportZoom

public function exportZoom($zoom, $value = '', $jForm = '')
{
    $js = 'var phocaStartZoom 	= ' . (int) $zoom . ';' . "\n" . 'var phocaZoom 		= null;' . "\n" . 'google.maps.event.addListener(' . $this->_map . ', "zoom_changed", function(phocaStartZoom, phocaZoom) {' . "\n" . 'phocaZoom = ' . $this->_map . '.getZoom();' . "\n";
    if ($value != '') {
        $js .= '   ' . $value . '.value = phocaZoom;' . "\n";
    } else {
        if ($jForm != '') {
            $js .= '   if (window.parent) window.parent.' . $jForm . '(phocaZoom);' . "\n";
        }
    }
    $js .= '});' . "\n";
    return $js;
}