When in MVI what would you do a thing that has no ...

# android-architecture

[ursus]

When in MVI
what would you do a thing that has no diff? Like lets say some list of dynamically added buttons in a horizontal scroll view and you want to select one (and show border around it for example)
by mvi it should be a click routed to viewmodel or wherever, where it copy mutates the state and emits a new tuple of list + selected index for example
but now what, what about the list? only the index basically changed. Do you teardown the whole buttons list and recreate?

[BMG]

Model would be like, data class Model(val list: List<Item>, val selectedIndex: Int). So, here, I would just update the selectedIndex and return the model without touching the list.

[BMG]

And in my render methods, I would check for list diffs and issue appropriate notify* methods if there is any change in list from the model. (In the above case, it would not touch the list)

[ursus]

Yes but in this case its not a recycler view but some linear layout with dynamically added views. Would you diff it manually?

[BMG]

Yeah. Since I always have access to previous model in my render(oldModel: Model, newModel: Model), I will diff it manually for those cases.

[ursus]

Btw similar issue is edit text.. every char typed is new State(val text) emitted..and then edittext.text = state.text.. it spams edit text too much and typing lags