AdaptiveResponsiveGrid class

A grid whose column count follows the width it is given.

The caller states the smallest acceptable width for one cell (minChildWidth); the widget fits as many columns as that allows. This is how a phone shows one or two cards per row and a tablet in landscape shows four, from a single call site.

AdaptiveResponsiveGrid(
  minChildWidth: 180,
  children: <Widget>[for (final Product p in products) ProductCard(p)],
)

More columns, not bigger text

Extra width buys extra cells. It never buys a larger fontSize: the text inside a cell keeps the size the user asked for, from AdaptiveTypography and the platform's accessibility setting. A grid that also inflated its type would break both design languages at once.

Measures its box, not the window

Column count comes from a LayoutBuilder, so the grid is correct inside a detail pane, an iPad Slide Over window or a dialog — places where the window width reported by MediaQuery is far wider than the space actually available.