swift - What does "Constrain to margins" mean in Interface Builder in Xcode 6.0.1 -

swift - What does "Constrain to margins" mean in Interface Builder in Xcode 6.0.1 -

i understand purpose of "spacing nearest neighbor" (in xcode 6, more in interface builder) what point of "constrain margins"?

is there link between "spacing nearest neighbor" border of particular command button, , fact of @ same time checking checkbox named "constrain margins"?

what role of feature in autolayout?

please find screenshot checkbox , label talking surrounded in reddish below:

(screenshot above in bigger format)

thank in advance answers 3 questions.

ios8 introduces new property of uiview: layoutmargins. shortly: these 4 values (a uiedgeinsets) represent margins of view: subviews can positioned relative these margins, or old way relative sides. wrote article in blog more details, allow me know if clear , if have additional doubts.

swift interface-builder autolayout xcode6 margins