Center UI elements in view with autolayout

问题

How do you use Autolayout to make a UI Element centered left-to-right when in both landscape and portrait mode? Can you have variables in autolayout?

回答1:

If you are using Interface builder to create & set position of your view, Select your View & do as the screenshot suggests below.

After that, click on "Add constraint" & you are done. This is just to set your view in horizontal centre. But you have to still add some more constraints. They are:

1. Height
2. Width
3. Distance from top/bottom layout guide/view.

Let me know if you don't know how to do this.

回答2:

set constraints both vertical and horizontal

more understand autolayout easily follow this link

http://www.raywenderlich.com/20881/beginning-auto-layout-part-1-of-2

output portait

output landscape

回答3:

in your xib ,you should add 3 constraints :

1. Hirizontal Center in Container；
2. Width ;
3. Height ;

来源：https://stackoverflow.com/questions/21793542/center-ui-elements-in-view-with-autolayout