apps-android-commons/app/src/main/res/layout/activity_custom_selector.xml

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

    <include
      layout="@layout/custom_selector_toolbar"
      android:id="@+id/toolbar"
      />

    <androidx.fragment.app.FragmentContainerView
      android:id="@+id/fragment_container"
      android:layout_width="match_parent"
      android:layout_height="0dp"
      app:layout_constraintBottom_toBottomOf="parent"
      app:layout_constraintTop_toBottomOf="@+id/toolbar_layout"/>

</androidx.constraintlayout.widget.ConstraintLayout>