How do I create multiple buttons on HTML5-generated panel?

I'm working to make an extension panel that works in Photoshop.

I've downloaded and installed Eclipse.

I've downloaded ExtensionBuilder3 and installed it into Eclipse.

I've created the "Demo" panel per the instructions using ExtensionBuilder3

I've changed the java code of the "Run ps code" button in the "Photoshop.jsx" file to change what the button does.

Now I want more buttons on the panel to do different things.

How do I create these?  I can't just copy the <li> element in the HTML for the panel.  This duplicates the button but it's not functional.  How do I create more buttons on the panel that can be matched with different Java scripts to do different things within Photoshop?