Check out example codes for "constraint barrier example". It will help you in understanding the concepts better.
Code Example 1
Let's have two buttons, @id/button1 and @id/button2. The constraint_referenced_ids field will reference them by simply having them as comma-separated list: <androidx.constraintlayout.widget.Barrier android:id="@+id/barrier" android:layout_width="wrap_content" android:layout_height="wrap_content" app:barrierDirection="bottom" app:constraint_referenced_ids="button1,button2" /> This way the barrier will allways be under button1 and button2.
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