How to set the XML attribute 'layout_constrainedWidth' of ConstraintLayout programmatically?

If you want to set constrainedWidth/Height programatically, then you've to take ConstraintLayout.LayoutParams for your view and set the flag named constrainedWidth or constrainedHeight at your will.

I.e.

ConstraintLayout.LayoutParams lp = (ConstraintLayout.LayoutParams) myView.getLayoutParams(); // View for which we need to set constrainedWidth.
lp.constrainedWidth = true/false;
myView.setLayoutParams(lp);

constrainedWidth

Specify if the horizontal dimension is constrained in case both left & right constraints are set and the widget dimension is not a fixed dimension.

By default, if a widget is set to WRAP_CONTENT, we will treat that dimension as a fixed dimension, meaning the dimension will not change regardless of constraints.

Setting this attribute to true allows the dimension to change in order to respect constraints.

Check out here.

I just figured this out.

So base on the answers above,

constrainedWidth can be accessed through ConstraintLayout.LayoutParams and thus can be altered by the following code: (Thank you @JeelVankhede)

ConstraintLayout.LayoutParams lp = (ConstraintLayout.LayoutParams) 
myView.getLayoutParams(); // View for which we need to set constrainedWidth.
lp.constrainedWidth = true/false;
myView.setLayoutParams(lp);

However when using ConstraintsSet the following code would be needed:

val constraintLayout = // your constraint layout
val constraintSet = ConstraintSet()
constraintSet.clone(constraintLayout)

// This is the imporatant part
constraint.constrainDefaultWidth(R.id.yourViewId, ConstraintSet.MATCH_CONSTRAINT_WRAP)

constraintSet.applyTo(constraintLayout)