down

top margin: 0

up

Most importantly, this example demonstrates at a basic
level how frames are used to create animations:
A frame is a single still image that can be used
within a sequence of other still images
to create the illusion of motion.
In this case, the first frame consists of a
ball centered on the screen,
and the second frame consists of the same ball
placed further down on the screen using
the top margin property.

PENDING: # image: a frame in Flutter