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kotlinlang

Hello. I am having trouble with react state. So basically I am handling a list to show outside of component and updating the state via callback like this.
```val (state, setState) = useState(emptyList&lt;Post&gt;())

provider.observePosts { list -&gt; setState(list) }```
With this method the ui only updates once, however if I set state like this `setState(list.toList())` it works fine.
I am concerning about performance. How should I update my list?

Don’t use a mutable list if you do - always pass a copy. Ideally at the point where the provider sends the update.

It’s possible that that’s the reason for what you observe. If you always pass the same `MutableList` instance then the `state` will change from `emptyList()` to your `MutableList` and then always stays the same.

I’m not sure if React compares old and new state and optimizes, but if it does it uses `===`.