sizeWithFont:constrainedToSize:lineBreakMode: deprecated in iOS7

Question

I\'m updating my app to iOS 7 and finally got it, but there\'s one thing I can\'t find a solution for.

In Xcode 4 I used the following method:

#defin         


        

Answer 1

If you're only supporting ios6 and later, you can convert your NSStrings to NSAttributedStrings and use NSAttributedString's boundingRectWithSize:options:context:.

Something that looked like this before:

CGSize size = [text sizeWithFont:font
               constrainedToSize:(CGSize){maxWidth, CGFLOAT_MAX}];

Could be easily converted to this and work in both ios6 and ios7:

NSAttributedString *attributedText =
    [[NSAttributedString alloc]
        initWithString:text
        attributes:@
        {
            NSFontAttributeName:    font
        }];
CGRect rect = [attributedText boundingRectWithSize:(CGSize){maxWidth, CGFLOAT_MAX}
                                           options:NSStringDrawingUsesLineFragmentOrigin
                                           context:nil];
CGSize size = rect.size;

As a side note, the benefit of doing things this way is so your text sizing in ios6 is now thread-safe. The old methods of sizeWithFont:... belonged to UIStringDrawing, which would crash if you ran sizeWithFont:... on two threads at the same time. In ios6, new NSStringDrawing functions for NSAttributedStrings were exposed and the boundingRectWithSize:... function is thread safe. I'm guessing this is why in ios7, the old sizeWithFont:... functions were deprecated.

Please note the documentation mentions:

In iOS 7 and later, this method returns fractional sizes (in the size component of the returned CGRect); to use a returned size to size views, you must use raise its value to the nearest higher integer using the ceil function.

So to pull out the calculated height or width to be used for sizing views, I would use:

CGFloat height = ceilf(size.height);
CGFloat width  = ceilf(size.width);