ListView, a column-like layout that automatically scrolls
  if its content is too long to fit the available space.
  For more information, see

Common layout widgets.

Aligning widgets

You control how a row or column aligns its children using the
mainAxisAlignment and crossAxisAlignment properties.
For a row, the main axis runs horizontally and the cross axis runs
vertically. For a column, the main axis runs vertically and the cross
axis runs horizontally.

The MainAxisAlignment and CrossAxisAlignment
enums offer a variety of constants for controlling alignment.

pubspec.yaml file or

Adding assets and images.
  You don’t need to do this if you’re referencing online
  images using