The Navigation Bar is a list of expandable items. Each item can be expanded by clicking on the header. A Navigation Bar with only one expandable item is sometimes also called Accordion. The Navigation Bar is very often used with email clients such as Microsoft Outlook or Gmail.
Angular Navigation bar with Multiple Items
By default the Angular Navigation Bar has only one expanded item. In order to configure the Navigation Bar to support multiple expanded item you have to set the ‘expandMode’ property to ‘multiple’.
With the multiple expanded item option switched on you can expand or collapse multiple items at the same time.
You can see a demo of multiple expanded items at: https://jqwidgets.com/angular/angular-navigationbar/angular-navigationbar-multipleexpanded.htm
