[4208] Improve performance of details view rendering on selection change

[AresEkb]

Bug: #4208

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[AresEkb]

When you select an object in a model, the FormBasedView is rendered 8 times. It works slow for complicated forms

I added memoization to FormBasedView

And also removed useState and useEffect from DetailsView. I think they only decrease performance, causes extra renderings. It worked as follows:

1. Selection is changed. So DetailsView is rendered
2. 1st useEffect compares current selection stored in state and new selection stored in context. And if they differ updates the state. I think there is no reason to store selection twice: in context and in state - context is enough. And also changing the state causes one more DetailsView rendering
3. On the next render objectIds will have a new value based on new selection. And useDetailsViewSubscription requests the new form
4. When the form payload is updated the 2nd useEffect is called and updates the state causing rerender
5. At last DetailsView is rendered with new state

I think that useSelection and useDetailsViewSubscription are enough to store the context/state. And local state is not required. Also useEffect combined with setState complicates logic and causes rerenderings

[sbegaudeau]

Unfortunately this improvement cannot be done, not all payload are or will be FormRefreshedEventPayload and as a result, we need to store the latest form in a state. If a new payload XXX is emitted by the backend, the form will become blank.

[AresEkb]

Thanks! I reverted the change

What do you think about currentSelection stored in local state? Should I revert it as well? I think it's not required, bacause useSelection() is just enough. We can get rid of some extra renderings removing currentSelection and corresponding useEffect() comparing selections