Removing/Adding constraint programmatically in ConstraintLayout

Question

I want to remove and add constraint programmatically based on some condition. Here are the screenshots:

and I want to remove it like this but in code:

so the same effect in want to achieve programmatically

and here is the code that I tried:

    if (advertisements.size() > 0) { //my own condition         ConstraintLayout.LayoutParams layoutParams = (ConstraintLayout.LayoutParams) btnCreateAd.getLayoutParams();         layoutParams.topToBottom = R.id.imvEmpty; //the imageview that is in center of the view         btnCreateAd.setLayoutParams(layoutParams);         recyclerView.setVisibility(View.VISIBLE);         txvMyAdEmptyText.setVisibility(View.GONE);         imvEmpty.setVisibility(View.GONE);         adapter.setList(advertisements);         adapter.notifyDataSetChanged();     } else {         ConstraintLayout.LayoutParams layoutParams = (ConstraintLayout.LayoutParams) btnCreateAd.getLayoutParams();         layoutParams.topToBottom = -1; //here i am trying to remove top constraint but it doesn't work         btnCreateAd.setLayoutParams(layoutParams);          recyclerView.setVisibility(View.GONE);         txvMyAdEmptyText.setVisibility(View.VISIBLE);         imvEmpty.setVisibility(View.VISIBLE);         adapter.setList(new ArrayList<Advertisement>());     }     mConstraintView.invalidate(); //this is my constraint view 

EDIT

I have tried using ConstraintSet also, but the result was even different somehow my RecyclerView (which is set to boundaries of parent view) was disappearing

 ConstraintSet set = new ConstraintSet();     set.clone(parentView);      if (advertisements.size() > 0) {          recyclerView.setVisibility(View.VISIBLE);         txvMyAdEmptyText.setVisibility(View.GONE);         imvEmpty.setVisibility(View.GONE);         adapter.setList(advertisements);         adapter.notifyDataSetChanged();      } else {          set.connect(btnCreateAd.getId(), ConstraintSet.TOP, imvEmpty.getId(), ConstraintSet.BOTTOM, 0);          recyclerView.setVisibility(View.GONE);         txvMyAdEmptyText.setVisibility(View.VISIBLE);         imvEmpty.setVisibility(View.VISIBLE);         adapter.setList(new ArrayList<Advertisement>());     }     set.connect(btnCreateAd.getId(), ConstraintSet.END, ConstraintSet.PARENT_ID, ConstraintSet.END, 0);     set.connect(btnCreateAd.getId(), ConstraintSet.START, ConstraintSet.PARENT_ID, ConstraintSet.START, 0);     set.connect(btnCreateAd.getId(), ConstraintSet.BOTTOM, ConstraintSet.PARENT_ID, ConstraintSet.BOTTOM, 0);      set.applyTo(parentView); 

Answer 1

I have not worked through your code, but the following illustrates how to break and make the constraint using ConstraintSet.

ConstraintSet set = new ConstraintSet(); ConstraintLayout layout;  layout = (ConstraintLayout) findViewById(R.id.layout); set.clone(layout); // The following breaks the connection. set.clear(R.id.bottomText, ConstraintSet.TOP); // Comment out line above and uncomment line below to make the connection. // set.connect(R.id.bottomText, ConstraintSet.TOP, R.id.imageView, ConstraintSet.BOTTOM, 0); set.applyTo(layout); 

Answer 2

Another way of doing this is with ConstraintLayout.LayoutParams.UNSET. This way is not using ConstraintSet.clear.

Assuming we want to remove the bottom constraint of our constraintLayout itself but can be any view:

val containerParams = cl_container.layoutParams as ConstraintLayout.LayoutParams containerParams.bottomToBottom = ConstraintLayout.LayoutParams.UNSET cl_container.layoutParams = containerParams