How to connect views in constraint layout that holds in different containers of coordinator layout?

Question

I have a fragment that has a CoordinatorLayout type of the main layout

    <?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">

<include
    android:id="@+id/secondContainer"
    android:layout_height="match_parent"
    android:layout_width="match_parent"
    app:layout_behavior="com.google.android.material.bottomsheet.BottomSheetBehavior"/>

<include
    android:id="@+id/mainContainer"
    layout="@layout/view_home_content"
    app:layout_anchorGravity="bottom"/>


</androidx.coordinatorlayout.widget.CoordinatorLayout>

So inside the main container I got two included separate layouts. First one

<androidx.constraintlayout.widget.ConstraintLayout
    android:id="@+id/topContainer"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
    <Button
        android:id="@+id/topButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>
</androidx.constraintlayout.widget.ConstraintLayout>

And the bottom one

<androidx.constraintlayout.widget.ConstraintLayout
    android:id="@+id/bottomContainer"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
    <TextView
        android:id="@+id/bottomText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>
</androidx.constraintlayout.widget.ConstraintLayout>

So my main goal is to make view with id topButton constraint to bottom of bottomText. I was trying to make it programmatically and it works fine if they are In the same xml file but when they are separate as I show above it doesn't work Here is how I programmatically connects them

with(binding.topContainer) {
        topContainer = topContainer
        button = topButton
    }

    with(binding.bottomContainer) {
        text = bottomText       
    }

    val mConstraintSet = ConstraintSet()
    mConstraintSet.clone(topContainer)
    mConstraintSet.clear(R.id.topButton, ConstraintSet.TOP)
    mConstraintSet.connect(R.id.topButton, ConstraintSet.TOP, R.id.bottomText, ConstraintSet.BOTTOM)
    mConstraintSet.applyTo(topContainer)

As I said earlier it works if I use ID's of layouts from one file. But this way seems they don't see each other

Answer 1

It's expected that It won't work when using the two separate files. To use constraints, you need to put the desired views inside the same constraint layout. You have a ConstraintLayout for bottom and another for top. You can try to put a ConstraintLayout inside your coordinatorLayout and try to put the constraints in include tags.