Replacement for deprecated sizeWithFont: in iOS 7?
In iOS 7, sizeWithFont: is now deprecated. How do I now pass in the UIFont object into the replacement method sizeWithAttributes: ?
Use sizeWithAttributes: instead, which now takes an NSDictionary . Pass in the pair with key UITextAttributeFont and your font object like this:
CGSize size = [string sizeWithAttributes:
@{NSFontAttributeName: [UIFont systemFontOfSize:17.0f]}];
// Values are fractional -- you should take the ceilf to get equivalent values
CGSize adjustedSize = CGSizeMake(ceilf(size.width), ceilf(size.height));
I believe the function was deprecated because that series of NSString+UIKit functions ( sizewithFont:... , etc) were based on the UIStringDrawing library, which wasn't thread safe. If you tried to run them not on the main thread (like any other UIKit functionality), you'll get unpredictable behaviors. In particular, if you ran the function on multiple threads simultaneously, it'll probably crash your app. This is why in iOS 6, they introduced a the boundingRectWithSize:... method for NSAttributedString . This was built on top of the NSStringDrawing libraries and is thread safe.
If you look at the new NSString boundingRectWithSize:... function, it asks for an attributes array in the same manner as a NSAttributeString . If I had to guess, this new NSString function in iOS 7 is merely a wrapper for the NSAttributeString function from iOS 6.
On that note, if you were only supporting iOS 6 and iOS 7, then I would definitely change all of your NSString sizeWithFont:... to the NSAttributeString boundingRectWithSize . It'll save you a lot of headache if you happen to have a weird multi-threading corner case! Here's how I converted NSString sizeWithFont:constrainedToSize: :
What used to be:
NSString *text = ...;
CGFloat width = ...;
UIFont *font = ...;
CGSize size = [text sizeWithFont:font
constrainedToSize:(CGSize){width, CGFLOAT_MAX}];
Can be replaced with:
NSString *text = ...;
CGFloat width = ...;
UIFont *font = ...;
NSAttributedString *attributedText =
[[NSAttributedString alloc] initWithString:text
attributes:@{NSFontAttributeName: font}];
CGRect rect = [attributedText boundingRectWithSize:(CGSize){width, CGFLOAT_MAX}
options:NSStringDrawingUsesLineFragmentOrigin
context:nil];
CGSize size = rect.size;
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);
正如你可以在苹果开发者网站上看到sizeWithFont ，它已被弃用，所以我们需要使用sizeWithAttributes 。
#define SYSTEM_VERSION_LESS_THAN(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedAscending)
NSString *text = @"Hello iOS 7.0";
if (SYSTEM_VERSION_LESS_THAN(@"7.0")) {
// code here for iOS 5.0,6.0 and so on
CGSize fontSize = [text sizeWithFont:[UIFont fontWithName:@"Helvetica"
size:12]];
} else {
// code here for iOS 7.0
CGSize fontSize = [text sizeWithAttributes:
@{NSFontAttributeName:
[UIFont fontWithName:@"Helvetica" size:12]}];
}
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