LayoutBuilder constructor Null safety

const LayoutBuilder(
  1. {Key? key,
  2. required Widget builder(
    1. BuildContext,
    2. BoxConstraints
    )}
)

Creates a widget that defers its building until layout.

The builder argument must not be null.

Implementation

const LayoutBuilder({
  super.key,
  required super.builder,
}) : assert(builder != null);