how to MODIFY a constraint layout programmatically?

Here is what I did (no need for ConstraintSet, we can work directly on the constraints themselves):

ConstraintLayout.LayoutParams params = (ConstraintLayout.LayoutParams) myView.getLayoutParams();
params.horizontalBias = 0.2f; // here is one modification for example. modify anything else you want :)
myView.setLayoutParams(params); // request the view to use the new modified params

it worked like a charm when I had a SeekBar and a TextView below it (aligned to it both left+right), and I wanted to update the TextView position to be under the SeekBar‘s cursor, so I had to update the horizontal bias params on the SeekBar‘s OnSeekBarChangeListener