[Navigator][0.19.0][ios][bug]: Scene Component will render twice and more

[osdio]

I have use rn before, and code a app in react-native. But the old rn don't rerender a component when pop back to the last scene.

But now I found that:

• when load to the initial route, the initial route will render, I mean the constructor will run once. +1
• when I push to another scene, the initial route component will render, the constructor will run once. +1
• after push to another scene, and then I pop this scene, and return to initial route, the constructor will run again after the scene didFocus. +1

So the scene state is losing, I don't know whether this is a functional to navigator, but I think this is a bug. It just like the web, it can't cache the last scene state, so and it make the navigator so slow.

[facebook-github-bot]

Hey soliury, thanks for reporting this issue!

React Native, as you've probably heard, is getting really popular and truth is we're getting a bit overwhelmed by the activity surrounding it. There are just too many issues for us to manage properly.

• If you don't know how to do something or something is not working as you expect but not sure it's a bug, please ask on StackOverflow with the tag react-native or for more real time interactions, ask on Discord in the #react-native channel.
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[osdio]

I have found that: every scene in navigator, it will unmount when push to another scene.

[osdio]

This must be a bug

[ndao]

+1

[chirag04]

dupe #3016