setChild method

@override void setChild(RenderObject? child)

Replace this object's single render child.

Implementations must be idempotent: passing the current child or a render object that is already adopted as a child of this parent must be a no-op.

Implementation

@override
void setChild(RenderObject? child) {
  if (child != null && child is! RenderBox) {
    throw ArgumentError(
      'RenderProxyBox children must be RenderBox, got ${child.runtimeType}',
    );
  }
  this.child = child as RenderBox?;
}