constraint dimension ratio

android:layout_width="0dp" or android:layout_height="0dp"

app:layout_constraintDimensionRatio="***:***"

 

example)

<ImageView
    android:id="@+id/main_banner"
    android:layout_width="match_parent"
    android:layout_height="0dp"
    android:layout_marginStart="20dp"
    android:layout_marginTop="44dp"
    android:layout_marginEnd="20dp"
    android:background="#26CBCBCB"
    android:backgroundTint="@color/white"
    android:scaleType="centerCrop"
    app:layout_constraintDimensionRatio="335:280"
    app:layout_constraintTop_toBottomOf="@+id/home_user_menu_layout"
    tools:layout_editor_absoluteX="20dp" />