I am having trouble remembering what kind of Android component is being used to make the selected list item menu in their Gmail app. That is, when I open the app and see the list of emails in the inbox, I can long-press one of the items, and some sort of list shows up in the top of the screen, sort of like a context menu, with actions I can perform on the selected item(s). I would like to replicate similar functionality in one of my own apps. If I recall correctly there is a way of doing this using some standard Android UI component, but I'm having trouble finding what that is. Any pointers?
You're looking for a contextual actions bar. Details on how to create one are stored under the menu section of the documentation as they relate to action items.