UIImageView和代码中的自动布局

Question

I'm trying to use programmatic visual constraints to display a label and a button next to one another. However, the UIImageView used as the button's background is making the intrinsic size of the button much too large.

I attempted to add a constraint that forces the height of the button to match the height of the label. But I just got a super tall label instead of a smaller button.

1. How do I set a constraint so that the button height is the same height as the label (and not vice-versa)
2. The button should keep the original aspect ratio of the image - its width should also match its own height (maybe this comes for free?)

Answer 1

The following works for this:

1. Set a width for the button in the visual layout: @"|-[titleLabel][refreshButton(==26)]"

2. Add a constraint such that the height of the button is equal to its own (now explicit) width:

     NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:refreshButton attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:refreshButton attribute:NSLayoutAttributeWidth multiplier:1.0f constant:0.0f]; 

I would still prefer a solution that uses the label's height, instead of a fixed value.