radius property

The size of the avatar, expressed as the radius (half the diameter).

If radius is specified, then neither minRadius nor maxRadius may be specified. Specifying radius is equivalent to specifying a minRadius and maxRadius, both with the value of radius.

If neither minRadius nor maxRadius are specified, defaults to 20 logical pixels. This is the appropriate size for use with ListTile.leading.

Changes to the radius are animated (including changing from an explicit radius to a minRadius/maxRadius pair or vice versa).