A gradient button initiates an immediate action related to a view, like adding or removing table rows. Gradient buttons contain icons—not text—and can be configured to behave as push buttons, toggles, or pop-up buttons. They usually reside in close proximity to (either within or beneath) their associated view.
Use gradient buttons in a view, not a window frame. Gradient buttons aren’t intended for use in toolbars or status bars. If you need a button in a toolbar, use a toolbar item. See Toolbars.
Prefer system-provided icons for gradient buttons because they’re familiar. Because system icons are template images, they automatically receive appropriate coloring in their default state and in response to user interaction. See Icons and Images > System Icons.
Avoid using labels to introduce gradient buttons. Because gradient buttons are closely connected with a specific view, their purpose is generally clear without the need for descriptive text.