The Telerik UI for JSP ExpansionPanel component is a tool best used when users want to focus on one out of several different sections on your screen. Information-rich web apps are the perfect host for this component as it naturally separates the information in a simple way. Wikipedia for example uses ExpansionPanels to divide each page into smaller sections to make it easier for users to read an article.
The control can be configured in several ways. By setting the appropriate attributes, you can override the title and subtitle, animate the component expansion or disable the component’s expandable property altogether.
Expanding and collapsing the control triggers three events—OnExpand, OnCollapse and OnComplete. The first two are emitted immediately when the corresponding action is requested (e.g. when the user clicks the expansion arrow). OnComplete is fired once the animation is completed which happens several parts of a second after the button click.
The Telerik ASP.NET JSP ExpansionPanel component has 20+ built-in themes such as Default (our own styling), Material (based on the Material Design guidelines) and Bootstrap (which looks like the Bootstrap styling to integrate better). You can easily customize any of out-of-the-box themes with a few lines of CSS or create new theme to match your colors and branding by using the Telerik SASS ThemeBuilder application.
Keyboard navigation can be enabled by adding a key-binding to focus on the ExpansionPanel and then use Space or Enter to toggle the expansion. If you have several expansion panel components, the user will be able to switch between them using Tab/Shift+Tab.