Hack navigation to alert

hack-navigation.jsx

function getActiveRouteName(navigationState) {
  if (!navigationState) {
    return null
  }
  const route = navigationState.routes[navigationState.index]
  // dive into nested navigators
  if (route.routes) {
    return getActiveRouteName(route)
  }
  return route.routeName
}

<Navigations
  onNavigationStateChange={(prevState, nextState) => {
    if (getActiveRouteName(prevState) === 'logout') {
      // Do something
      alert('Logout')
    }
  }}
/>