alignment property
alignment positions the child within the RippleContainer.
When null, the RippleContainer sizes itself to the child (like a plain
Container). If a width or height is provided on the RippleContainer
and alignment is left null, the child is centered by default.
Set this explicitly (e.g. Alignment.centerLeft) to control child placement, or set it to null together with an explicit size to keep the child top-left aligned.
Implementation
final Alignment? alignment;