Create a Table of Contents
A table of contents (TOC) shows an outline of survey contents and helps users to quickly navigate through longer surveys. To display a TOC, enable the showTOC property. You can also specify tocLocation: "left" or "right".
A TOC displays page titles or page names if the titles are undefined. However, each page can also include a title specifically for the TOC. To define this title, use the navigationTitle property.