shadcn-ui/apps/v4/examples/radix/dropdown-menu-submenu.tsx

import { Button } from "@/examples/radix/ui/button"
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuGroup,
  DropdownMenuItem,
  DropdownMenuPortal,
  DropdownMenuSeparator,
  DropdownMenuShortcut,
  DropdownMenuSub,
  DropdownMenuSubContent,
  DropdownMenuSubTrigger,
  DropdownMenuTrigger,
} from "@/examples/radix/ui/dropdown-menu"

export function DropdownMenuSubmenu() {
  return (
    <DropdownMenu>
      <DropdownMenuTrigger asChild>
        <Button variant="outline">Open</Button>
      </DropdownMenuTrigger>
      <DropdownMenuContent>
        <DropdownMenuGroup>
          <DropdownMenuItem>Team</DropdownMenuItem>
          <DropdownMenuSub>
            <DropdownMenuSubTrigger>Invite users</DropdownMenuSubTrigger>
            <DropdownMenuPortal>
              <DropdownMenuSubContent>
                <DropdownMenuItem>Email</DropdownMenuItem>
                <DropdownMenuItem>Message</DropdownMenuItem>
                <DropdownMenuSub>
                  <DropdownMenuSubTrigger>More options</DropdownMenuSubTrigger>
                  <DropdownMenuPortal>
                    <DropdownMenuSubContent>
                      <DropdownMenuItem>Calendly</DropdownMenuItem>
                      <DropdownMenuItem>Slack</DropdownMenuItem>
                      <DropdownMenuSeparator />
                      <DropdownMenuItem>Webhook</DropdownMenuItem>
                    </DropdownMenuSubContent>
                  </DropdownMenuPortal>
                </DropdownMenuSub>
                <DropdownMenuSeparator />
                <DropdownMenuItem>Advanced...</DropdownMenuItem>
              </DropdownMenuSubContent>
            </DropdownMenuPortal>
          </DropdownMenuSub>
          <DropdownMenuItem>
            New Team
            <DropdownMenuShortcut>⌘+T</DropdownMenuShortcut>
          </DropdownMenuItem>
        </DropdownMenuGroup>
      </DropdownMenuContent>
    </DropdownMenu>
  )
}