* @param 'labels' The corresponding labels to show for the checked items.
* @param 'oncheck' Callback function which will be called when a checkbox/radiobutton is selected. If the function returns false the input will be unchecked.
* @param 'onuncheck' @see 'oncheck'.
* @param 'singleSelect' If true radiobuttons will be used instead of checkboxes.
* @param 'singleSelect' If true radiobuttons will be used instead of checkboxes.