Indicates whether to preserve the aspect ratio of the original image
when scaling to fit the image within the bounding box provided by
width and height.
If set to true, it affects the dimensions of this Image
in the following way:
width is set, height is scaled to preserve ratio
height is set, width is scaled to preserve ratio
width and height may be different from the
initially set values if they needed to be adjusted to preserve aspect
ratio.
If unset or set to false, it affects the dimensions of this
ImageView in the following way:
width is set, the image's width is scaled to
match and height is unchanged;
height is set, the image's height is scaled to
match and height is unchanged;
width and height.
Diagram: Image