具有自动布局的iOS旋转

Question

I just followed Swift Ios tutorial on Itunes (Stanford University CS193p)

I followed the first example to make a calculator.

1.I add the button to the screen and set the auto layout attributes.

2.then the warning comes out, and I update the frames with the constraints.

3.The I start the simulator, it seems works fine.

4. But when I rotated the screen, all the number buttons get to heap together.

I know it must be made by some small mistakes, even I carefully followed the tutorial. Because I am new to ios, and thought this problem is really hard to describe, so I just put it there. Hopefully, there is some one could solve this problem.

Answer 1

You have this problem because you made the constraints using the wAny hRegular size class. When you rotate to landscape, the height is now compact, and you don't have any constraints for that size class (so all the buttons have {0,0} origin). You should make separate constraints for that size class, probably with 3 rows of 4 rather than 4 rows of 3 to fit the shorter space better.