selectedIcon property
final
The optional Widget (usually an Icon) that's displayed when this NavigationDestination is selected.
If selectedIcon is non-null, the destination will fade from icon to selectedIcon when this destination goes from unselected to selected.
The icon will use NavigationBarThemeData.iconTheme with WidgetState.selected. If this is null, the default IconThemeData would use a size of 24.0 and ColorScheme.onSurface.
Implementation
final Widget? selectedIcon;