Question about ViewState instantiation
ranhsd opened this issue · comments
Hi @cardoso , Really like this example... Good job!
I only have one question. I noticed that you created ViewState objects which receive the main state and return the state for the specific view. I tried to test your app and noticed that the ViewState objects (for example: MovieListViewState) init function is being called several times. Actually it is being called when any action is being dispatched and I don't know if it is a best practice.
Did you noticed that while developing this example?
BTW! I tried to integrate skipRepeats into your project by implementing the Equatable protocol but its still calling the init function a lot of times
Hi @ranhsd !
When an action is dispatched, it rebuilds the entire state of the application and triggers a re-render of all views. This is intrinsic to the redux pattern.
In case it becomes a burden for performance, it's possible to implement workarounds such as skipRepeats or decide whether or not to re-render a view inside the newState(state:) method.
This is a challenge faced in web development as well: https://stackoverflow.com/questions/41763031/how-to-prevent-react-from-re-rendering-the-whole-component
Hi @cardoso you're right. But in ReSwift you have the ability to skipRepeats and in your it is not implemented.
@ranhsd I can take a look into implementing it in the weekend.
But if you can submit a PR, I'll be happy to merge it. :)
Thanks for the suggestion!
Hi,
since ReSwift 4.0.1 skipRepeats is on by default when the SubStates are Equatable. After doing this, I tested it and newState for MovieList and MovieDetail is called a few times less. So I hope it's fine, if I add a PR to make the two ViewStates Equatable.
@cardoso Should this issue stay open or can it be closed?
Closed. Thanks @fbernutz