buttons and uipicker not visible on the view

I have create a new single view application and have added button and uipicker to the view howeve i cannot see the edges of the buttons and picker.

Once I build and run the application i cannot see the uipicker on the iphone app. Please help and advise how to solve this issue.

I using OS X Yosemite and XCode 6.3.2. Tried different iphone on the ios simulator but still not able to view correctly.

What layout constraints did you add to your views? You must add sufficient constraints for the layout engine to be able to determine the horizontal and vertical position and size.


Were there any warnings about ambiguous layout in the console?

buttons and uipicker not visible on the view
 
 
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