NSLayoutConstraint(CompactConstraint)

@interface NSLayoutConstraint (CompactConstraint)

NSLayoutConstraint (CompactConstraint), a class category from Marco Arment’s CompactConstraint library, is integrated with Cephei. CompactConstraint provides an Auto Layout grammar and methods that are easier to use and understand than UIKit’s built in functions for programmatically adding constraints.

Refer to its readme to learn how to use it. There are two changes to note: most importantly, the methods have an hb_ prefix, and two methods that are marked as deprecated in the original project have been removed.

CompactConstraint is licensed under the MIT License.

  • Instantiate a single constraint with the compact syntax.

    Declaration

    Objective-C

    + (instancetype)hb_compactConstraint:(NSString *)relationship
                             metrics:
                                 (NSDictionary<NSString *, NSNumber *> *)metrics
                               views:(NSDictionary<NSString *, UIView *> *)views
                                self:(id)selfView;

    Swift

    class func hb_compactConstraint(_ relationship: String!, metrics: [String : NSNumber]!, views: [String : UIView]!, self selfView: Any!) -> Self!

  • Instantiate any number of constraints. Can also mix in Visual Format Language strings.

    Declaration

    Objective-C

    + (NSArray<NSLayoutConstraint *> *)
    hb_compactConstraints:(NSArray<NSString *> *)relationshipStrings
                  metrics:(NSDictionary<NSString *, NSNumber *> *)metrics
                    views:(NSDictionary<NSString *, UIView *> *)views
                     self:(id)selfView;

    Swift

    class func hb_compactConstraints(_ relationshipStrings: [String]!, metrics: [String : NSNumber]!, views: [String : UIView]!, self selfView: Any!) -> [NSLayoutConstraint]!

  • And a convenient shortcut for creating constraints with the visualFormat string as the identifier

    Declaration

    Objective-C

    + (NSArray<NSLayoutConstraint *> *)
    hb_identifiedConstraintsWithVisualFormat:(NSString *)format
                                     options:(NSLayoutFormatOptions)opts
                                     metrics:(NSDictionary<NSString *,
                                                           NSNumber *> *)metrics
                                       views:(NSDictionary<NSString *, UIView *>
                                                  *)views;

    Swift

    class func hb_identifiedConstraints(withVisualFormat format: String!, options opts: NSLayoutConstraint.FormatOptions = [], metrics: [String : NSNumber]!, views: [String : UIView]!) -> [NSLayoutConstraint]!