handlekeydown-01-51.js

hanldeKeyup(evt) {
    //...more code...
}

hanldeKeydown(evt) {
  const { cursor, searchItems } = this.state;
  // arrow up/down button should select next/previous list element
  if (evt.keyCode === 38 && cursor > 0) {
    this.setState(prevState => ({
      cursor: prevState.cursor - 1
    }));
  } else if (evt.keyCode === 40 && cursor < searchItems.length - 1) {
    this.setState(prevState => ({
      cursor: prevState.cursor + 1
    }));
  }
}