debugRenderObjectPassthrough property
Whether this widget is intentionally transparent to render-object layouts.
Render-object parents (for example Row, Column, and Stack) flatten
non-render descendants to collect concrete render objects. Widgets that
extend Widget directly and rely on view for visual output are dropped
during that flattening step. Such visual wrappers should instead extend
StatelessWidget, StatefulWidget, or RenderObjectWidget.
Set this to true only for wrappers that deliberately pass through all
rendering to descendants (for example flex/stack parent-data wrappers).
Implementation
@override
bool get debugRenderObjectPassthrough => true;