Round Android buttons with Cardview

view.xml

<androidx.cardview.widget.CardView
    android:id="@+id/btnClear"
    android:layout_width="64dp"
    android:layout_height="64dp"
    android:layout_marginEnd="16dp"
    android:background="@drawable/ic_baseline_save_alt_24"
    android:clickable="true"
    android:contentDescription="@string/main_button_text"
    android:foreground="?android:attr/selectableItemBackground"
    app:cardBackgroundColor="?colorPrimary"
    app:cardCornerRadius="32dp"
    app:layout_constraintTop_toTopOf="@id/btnMain"
    app:layout_constraintBottom_toBottomOf="@id/btnMain"
    app:layout_constraintEnd_toStartOf="@id/btnMain">

    <ImageView
        android:id="@+id/ivBtnClear"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:padding="16dp"
        android:src="@drawable/ic_baseline_close_24"
        app:tint="@color/black" />
</androidx.cardview.widget.CardView>