The content is resized to fit the bounds rectangle, preserving the aspect of the content. If the content does not completely fill the bounds rectangle, the content is centered in the partial axis.
Available in Mac OS X v10.5 and later.
Declaration Syntax Version Information- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)