Widget _buildImageRow(int imageIndex) => Row(
      children: [
        _buildDecoratedImage(imageIndex),
        _buildDecoratedImage(imageIndex + 1),
      ],
    );

You can find more Container examples in the tutorial
and the Flutter Gallery (running app, repo).

App source: container

GridView

Use GridView to lay widgets out as a two-dimensional
list. GridView provides two pre-fabricated lists,
or you can build your own custom grid. When a GridView
detects that its contents are too long to fit the render box,
it automatically scrolls.

Summary (GridView)

Lays widgets out in a grid

Detects when the column content exceeds the render box
and automatically provides scrolling