Programmatic view creation and VISIBILITY_MODE_IGNORE about constraintlayout HOT 3 CLOSED

ConstraintSets are not designed for frame by frame apply.
ConstraintLayout is a linear equation solver. It will be slow if you update every frame managing 28 widgets.
If you are changing visibility frequently (especially to Gone).
Reactive frameworks like compose work by doing a diff on your update.
ConstraintSet it not built that way. (And to some extent ConstraintLayout could be slow to)
You could reduce your change by using ConstraintProperties which are per view.

from constraintlayout.

I need a little more details:
I am not sure ConstraintSet.VISIBILITY_MODE_IGNORE is relevant to ConstraintLayout
What are you hoping to achieve by setting it?
Why are you maintaining the ConstraintSet?
Why

 if (isFirstRender) {
            constraintSet.setVisibility(view.id, View.GONE)
        } else {
            view.visibility = View.GONE
        }

Not

            constraintSet.setVisibility(view.id, View.GONE)
            view.visibility = View.GONE

?

from constraintlayout.

Yep, i didin't mention that during init i setting up relations between generated views. e.g.

constraintSet.connect(labelId, ConstraintSet.START, inputId, ConstraintSet.START)

Overall overview:
There is a virtualFlow with couple inputs in a chain, each of input has "connected" label and error TextViews.
UI is driven by state: LiveData + monolith state of whole screen which renders on every change. Current View Framework doesn't friendly for such approach so there is a lot of optimisations inside my observe function aka "render state". For example, i can "calculate diff" between old and new states and update only small part of my view tree, e.g. one input + connected label and error.
So render state will looks like:

val itemToUpdate = magicDiffAlrgorithm(state)
if (itemToUpdate.isVisible) {
   view.visibility = View.VISIBLE
} else {
   view.visibility = View.GONE
}
...
view.text = itemToUpdate.title
// and so on

In this case view.visibility = View.GONE will works fast, while constraintSet.setVisibility(view.id, View.GONE) breaks this idea due to nature of constraintSet.applyTo(..). I can't use it for frequent changes cuz it leads to performance issues.

P.S. issue partially solved by checks on false-positive updates e.g.

fun View.show(): View {
    if (visibility == View.VISIBLE) return
    visibility = View.VISIBLE
} // or similar via ConstraintSet.getVisibility(int viewId)

But it doesn't helps if you realy need to change visibility frequintly. The worst part is that i forced to use both approaches: ConstraintSet for first frame draw and eficient for rest ones.MVI

P.S. i chose such architecture with manual diffing to more seamless migration to compose wihtout diving in heavy frameworks like MVICore or Litho

from constraintlayout.