"navigation" prop in transition

navigation-prop-in-transition.js

// The 'navigation' prop passed to PhotoGrid
navigation: {
  ...
  state: {
    routeName: 'PhotoGrid',
    ...
    transition: {  // transition is only present if it's current in transition
      toRoute: 'PhotoDetail'
    }
  }
}

// The 'navigation' prop passed to PhotoDetail
navigation: {
  ...
  state: {
    routeName: 'PhotoDetail',
    ...
    transition: {  // transition is only present if it's current in transition
      fromRoute: 'PhotoGrid'
    }
  }
}