How to put text view in the center of the layout if second Textview visibility is gone?

Question

How to put text view in the center of the layout if second Textview visibility is gone?

I have attached a layout that I draw by hand.

I have there two Textview inside lets say ConstraintLayout

I want to write an xml that in situation that there are two visible TextViews sets margin and constraint according to numbers in screenshot but in case TextView2 visibility is gone I want to put TextView1 in the center of the layout.

Can someone help me with that?

  <?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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">

    <TextView>
        android:id="@+id/TextView1”
        android:layout_width=“100dp”
        android:layout_height="wrap_content"
        android:text=“TextView”1
        app:layout_constraintStart_toStartOf="parent"
        android:layout_marginStart=“16dp"
        />

 <TextView>
        android:id="@+id/TextView2”
        android:layout_width=“100dp”
        android:layout_height="wrap_content"
        android:text=“TextView”1
        app:layout_constraintEnd_toEndOf=“parent”
        app:layout_constraintStart_toStartOf=“@id/TextView1”
        android:layout_marginStart=“20dp"
        android:layout_marginEnd“8dp"
        />
</androidx.constraintlayout.widget.ConstraintLayout>

Answer 1

Place the two TextViews in a horizontal chain with the chain style set to spread_inside. Now, when the right TextView is set to gone, the left TextView assumes the right constraint of the right TextView with a new margin set to 16dp (app:layout_goneMarginEnd="16dp" ).

See Margins when connected to a GONE widget.

<androidx.constraintlayout.widget.ConstraintLayout 
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/TextView1"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:text="TextView1"
        app:layout_constraintEnd_toStartOf="@+id/TextView2"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintHorizontal_chainStyle="spread_inside"
        app:layout_goneMarginEnd="16dp" />

    <TextView
        android:id="@+id/TextView2"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:text="TextView2"
        app:layout="@id/TextView1"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@+id/TextView1"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>