React Navigation with MobX
Paul Xue

Hi Paul, thanks for the article!

I get the following error:

“undefined ist not an object (evaluating ‘state.params’)

in this line of App.js:

“ return {title: state.params && state.params.title}”

Do you have any idea how to fix this? I also grabbed your code from github and tried running it exactly as it is, however I still get the error.

I’m using Expo if that’s of any importance.

Thanks :)

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