function ZmenVyber(formular_id)
{
	prehled_zapasu = document.getElementById(formular_id).elements;
		
	if (prehled_zapasu != null)
		for (i = 0; i < prehled_zapasu.length; i++)
		{
	 		if (prehled_zapasu[i].type == "checkbox")
				if (prehled_zapasu[i].disabled != true)
					prehled_zapasu[i].checked = 1;
		}
}