Close other pickers

As a rule, all other pickers should be closed when another picker opens.
In the following example, two state variables are defined for country and city pickers. When the country picker opens, the city picker closes, and the same happens inside the onOpen callback of the city picker.

function App() {
  const [countryOpen, setCountryOpen] = useState(false);
  const [cityOpen, setCityOpen] = useState(false);

  const onCountryOpen = useCallback(() => {
    setCityOpen(false);
  }, []);

  const onCityOpen = useCallback(() => {
    setCountryOpen(false);
  }, []);

  return (
    // Country
    <DropDownPicker
      open={countryOpen}
      onOpen={onCountryOpen}
      ...
    />

    // City
    <DropDownPicker
      open={cityOpen}
      onOpen={onCityOpen}
      ...
    />
  );
}