title: Layout inside include always null inside adapter
body: <p>I am showing a list of items in a recycler view.
  The item_layout.xml has an include which its parent is a ContraintLayout and it has some elements inside which i can point to them easily by view.elementID</p>
  
  <pre><code>&lt;androidx.constraintlayout.widget.ConstraintLayout...&gt;
  
  ...
  
        &lt;include
          android:id="@+id/incNumberPicker"
          layout="@layout/number_picker"
          android:layout_width="0dp"
          android:layout_height="wrap_content"
          android:layout_marginTop="@dimen/padding_big"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/lblFamily"
          app:layout_constraintWidth_percent="0.5" /&gt;
  
  
  ...
  &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  </code></pre>
  
  <p>I can get the reference of the include layout but not on the parent layout of this include.
  and I tried...</p>
  
  <pre><code>    private val incNumberPicker =  view.findViewById&lt;ConstraintLayout&gt;(R.id.incNumberPicker) (not null)
      private val bgNumberPicker = view.bgNumberPicker (null)
      private val bgNumberPicker =  incNumberPicker.findViewById&lt;ConstraintLayout&gt;(R.id.bgNumberPicker) (null)
      private val bgNumberPicker = view.findViewById&lt;ConstraintLayout&gt;(R.id.bgNumberPicker)(null)
  </code></pre>
  
  <p>This is my include layout</p>
  
  <pre><code>&lt;androidx.constraintlayout.widget.ConstraintLayout
      android:id="@+id/bgNumberPicker"
      xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      android:layout_width="match_parent"
      android:focusableInTouchMode="true"
      android:layout_height="wrap_content"
      android:background="@drawable/number_picker_bg"&gt;
  
  
      &lt;EditText
          android:id="@+id/etNumber"
          style="@style/et_number_picker"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_marginStart="@dimen/padding_normal"
          android:layout_marginEnd="@dimen/padding_normal"
          android:backgroundTint="@android:color/transparent"
          android:inputType="number"
          android:maxLength="3"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintEnd_toStartOf="@+id/btnAdd"
          app:layout_constraintStart_toEndOf="@+id/btnRemove"
          app:layout_constraintTop_toTopOf="parent" /&gt;
  </code></pre>
  
  <p>This parent constraint has a background which I want to change the color depending on the state, so I want to enadle/disable this constraintlayout. the thing is I can point the rest of the elements very easily with a normal view.etNumber but not to the parent constraint.</p>
  
  <p>UPDATE trace error</p>
  
  <pre><code>E/AndroidRuntime: FATAL EXCEPTION: main
  Process: dev.game.jupiter, PID: 29108
  java.lang.IllegalStateException: bgNumberPicker must not be null
      at es.game.jupiter.ui.inventory.productsCounter.InventoriedProductAdapter$InventoriedProductViewHolder.setLocationPickerEditable(InventoriedProductAdapter.kt:95)
      at es.game.jupiter.ui.inventory.productsCounter.InventoriedProductAdapter$InventoriedProductViewHolder.hideShowOptions(InventoriedProductAdapter.kt:85)
      at es.game.jupiter.ui.inventory.productsCounter.InventoriedProductAdapter$InventoriedProductViewHolder$3.onClick(InventoriedProductAdapter.kt:65)
      at android.view.View.performClick(View.java:5205)
  </code></pre>
  
  <p>Thanks for any help.</p>