NSLayoutConstraint(MMMTemple)

@interface NSLayoutConstraint (MMMTemple)

/**
 * Our wrapper over the corresponding method of NSLayoutConstraint extending the visual layout language a bit to support
 * `safeAreaLayoutGuide` property introduced in iOS 11 and still be compatible with older versions of iOS.
 * (See also `mmm_safeAreaLayoutGuide` in our extension of UIView.)
 *
 * To use it simply replace a reference to the superview edge "|" with a reference to a safe edge "<|".
 *
 * For example, if you have the following pre iOS 9 code:
 *
 * \code
 * [NSLayoutConstraint activateConstraints:[NSLayoutConstraint
 *     constraintsWithVisualFormat:@"V:[_button]-(normalPadding)-|"
 *     options:0 metrics:metrics views:views
 * ]];
 * \endcode
 *
 * And now you want to make sure that the button sits above the safe bottom margin on iPhone X, then do this:
 *
 * \code
 * [NSLayoutConstraint activateConstraints:[NSLayoutConstraint
 *     mmm_constraintsWithVisualFormat:@"V:[_button]-(normalPadding)-<|"
 *     options:0 metrics:metrics views:views
 * ]];
 * \endcode
 *
 * That's it. It'll anchor the button to the bottom of its superview on iOS 9 and 10, but anchor it to the bottom of
 * its safeAreaLayoutGuide on iOS 11.
 *
 * Please note that using "|>" to pin to the top won't exclude the status bar on iOS 9 and 10.
 */
+ (NSArray<NSLayoutConstraint *> *)mmm_constraintsWithVisualFormat:(NSString *)format
	options:(NSLayoutFormatOptions)opts
	metrics:(nullable NSDictionary<NSString *,id> *)metrics
	views:(nullable NSDictionary<NSString *,id> *)views;

/** A shortcut for `[NSLayoutConstraint activateConstraints:[NSLayoutConstraint mmm_constraintsWithVisualFormat:...`. */
+ (void)mmm_activateConstraintsWithVisualFormat:(NSString *)format
	options:(NSLayoutFormatOptions)opts
	metrics:(nullable NSDictionary<NSString *,id> *)metrics
	views:(nullable NSDictionary<NSString *,id> *)views;

/** Missing counterparts for (de)activateConstraints, so constraint activation code looks the same for individual constraints. */
+ (void)activateConstraint:(NSLayoutConstraint *)constraint;
+ (void)deactivateConstraint:(NSLayoutConstraint *)constraint;

/** A missing convenience initializer including priority. */
+ (instancetype)constraintWithItem:(id)view1 attribute:(NSLayoutAttribute)attr1
	relatedBy:(NSLayoutRelation)relation
	toItem:(nullable id)view2 attribute:(NSLayoutAttribute)attr2
	multiplier:(CGFloat)multiplier constant:(CGFloat)c
	priority:(UILayoutPriority)priority;

/** A missing convenience initializer allowing to set identifier for this constraint. */
+ (instancetype)constraintWithItem:(id)view1 attribute:(NSLayoutAttribute)attr1
	relatedBy:(NSLayoutRelation)relation
	toItem:(nullable id)view2 attribute:(NSLayoutAttribute)attr2
	multiplier:(CGFloat)multiplier constant:(CGFloat)c
	identifier:(NSString *)identifier;

/** A missing convenience initializer allowing to set both priority and identifier for this constraint. */
+ (instancetype)constraintWithItem:(id)view1 attribute:(NSLayoutAttribute)attr1
	relatedBy:(NSLayoutRelation)relation
	toItem:(nullable id)view2 attribute:(NSLayoutAttribute)attr2
	multiplier:(CGFloat)multiplier constant:(CGFloat)c
	priority:(UILayoutPriority)priority
	identifier:(NSString *)identifier;

/** A missing convenience initializer allowing to tag a bunch of visual constraints with the same identifier. */
+ (NSArray<__kindof NSLayoutConstraint *> *)constraintsWithVisualFormat:(NSString *)format
	options:(NSLayoutFormatOptions)opts
	metrics:(nullable NSDictionary<NSString *,id> *)metrics
	views:(nullable NSDictionary<NSString *, id> *)views
	identifier:(NSString *)identifier DEPRECATED_ATTRIBUTE;

@end

Undocumented

+mmm_constraintsWithVisualFormat:options:metrics:views:
Our wrapper over the corresponding method of NSLayoutConstraint extending the visual layout language a bit to support safeAreaLayoutGuide property introduced in iOS 11 and still be compatible with older versions of iOS. (See also mmm_safeAreaLayoutGuide in our extension of UIView.)

To use it simply replace a reference to the superview edge “|” with a reference to a safe edge “<|”.

For example, if you have the following pre iOS 9 code:

\code [NSLayoutConstraint activateConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@“V:[_button]-(normalPadding)-|” options:0 metrics:metrics views:views ]]; \endcode

And now you want to make sure that the button sits above the safe bottom margin on iPhone X, then do this:

\code [NSLayoutConstraint activateConstraints:[NSLayoutConstraint mmm_constraintsWithVisualFormat:@“V:[_button]-(normalPadding)-<|” options:0 metrics:metrics views:views ]]; \endcode

That’s it. It’ll anchor the button to the bottom of its superview on iOS 9 and 10, but anchor it to the bottom of its safeAreaLayoutGuide on iOS 11.

Please note that using “|>” to pin to the top won’t exclude the status bar on iOS 9 and 10.
Declaration
Objective-C

+ (nonnull NSArray<NSLayoutConstraint *> *) mmm_constraintsWithVisualFormat:(nonnull NSString *)format options:(NSLayoutFormatOptions)opts metrics: (nullable NSDictionary<NSString *, id> *)metrics views:(nullable NSDictionary<NSString *, id> *) views;
Swift

class func mmm_constraints(withVisualFormat format: String, options opts: NSLayoutConstraint.FormatOptions = [], metrics: [String : Any]?, views: [String : Any]?) -> [NSLayoutConstraint]


                    
                    
                    +mmm_activateConstraintsWithVisualFormat:options:metrics:views:

A shortcut for [NSLayoutConstraint activateConstraints:[NSLayoutConstraint mmm_constraintsWithVisualFormat:....

Declaration

Objective-C

+ (void)
    mmm_activateConstraintsWithVisualFormat:(nonnull NSString *)format
                                    options:(NSLayoutFormatOptions)opts
                                    metrics:(nullable NSDictionary<NSString *,
                                                                   id> *)metrics
                                      views:(nullable NSDictionary<NSString *,
                                                                   id> *)views;

Swift

class func mmm_activateConstraints(withVisualFormat format: String, options opts: NSLayoutConstraint.FormatOptions = [], metrics: [String : Any]?, views: [String : Any]?)

+activateConstraint:
Missing counterparts for (de)activateConstraints, so constraint activation code looks the same for individual constraints.
Declaration
Objective-C

+ (void)activateConstraint:(nonnull NSLayoutConstraint *)constraint;
Swift

class func activate(_ constraint: NSLayoutConstraint)


                    
                    
                    +deactivateConstraint:

Undocumented

Declaration

Objective-C

+ (void)deactivateConstraint:(NSLayoutConstraint *)constraint;

Swift

class func deactivate(_ constraint: NSLayoutConstraint)


                    
                    
                    +constraintWithItem:attribute:relatedBy:toItem:attribute:multiplier:constant:priority:

A missing convenience initializer including priority.

Declaration

Objective-C

+ (nonnull instancetype)constraintWithItem:(nonnull id)view1
                                 attribute:(NSLayoutAttribute)attr1
                                 relatedBy:(NSLayoutRelation)relation
                                    toItem:(nullable id)view2
                                 attribute:(NSLayoutAttribute)attr2
                                multiplier:(CGFloat)multiplier
                                  constant:(CGFloat)c
                                  priority:(UILayoutPriority)priority;

Swift

convenience init(item view1: Any, attribute attr1: NSLayoutConstraint.Attribute, relatedBy relation: NSLayoutConstraint.Relation, toItem view2: Any?, attribute attr2: NSLayoutConstraint.Attribute, multiplier: CGFloat, constant c: CGFloat, priority: UILayoutPriority)


                    
                    
                    +constraintWithItem:attribute:relatedBy:toItem:attribute:multiplier:constant:identifier:

A missing convenience initializer allowing to set identifier for this constraint.

Declaration

Objective-C

+ (nonnull instancetype)constraintWithItem:(nonnull id)view1
                                 attribute:(NSLayoutAttribute)attr1
                                 relatedBy:(NSLayoutRelation)relation
                                    toItem:(nullable id)view2
                                 attribute:(NSLayoutAttribute)attr2
                                multiplier:(CGFloat)multiplier
                                  constant:(CGFloat)c
                                identifier:(nonnull NSString *)identifier;

Swift

convenience init(item view1: Any, attribute attr1: NSLayoutConstraint.Attribute, relatedBy relation: NSLayoutConstraint.Relation, toItem view2: Any?, attribute attr2: NSLayoutConstraint.Attribute, multiplier: CGFloat, constant c: CGFloat, identifier: String)


                    
                    
                    +constraintWithItem:attribute:relatedBy:toItem:attribute:multiplier:constant:priority:identifier:

A missing convenience initializer allowing to set both priority and identifier for this constraint.

Declaration

Objective-C

+ (nonnull instancetype)constraintWithItem:(nonnull id)view1
                                 attribute:(NSLayoutAttribute)attr1
                                 relatedBy:(NSLayoutRelation)relation
                                    toItem:(nullable id)view2
                                 attribute:(NSLayoutAttribute)attr2
                                multiplier:(CGFloat)multiplier
                                  constant:(CGFloat)c
                                  priority:(UILayoutPriority)priority
                                identifier:(nonnull NSString *)identifier;

Swift

convenience init(item view1: Any, attribute attr1: NSLayoutConstraint.Attribute, relatedBy relation: NSLayoutConstraint.Relation, toItem view2: Any?, attribute attr2: NSLayoutConstraint.Attribute, multiplier: CGFloat, constant c: CGFloat, priority: UILayoutPriority, identifier: String)


                    
                    
                    +constraintsWithVisualFormat:options:metrics:views:identifier:

Deprecated

A missing convenience initializer allowing to tag a bunch of visual constraints with the same identifier.

Declaration

Objective-C

+ (nonnull NSArray<__kindof NSLayoutConstraint *> *)
    constraintsWithVisualFormat:(nonnull NSString *)format
                        options:(NSLayoutFormatOptions)opts
                        metrics:(nullable NSDictionary<NSString *, id> *)metrics
                          views:(nullable NSDictionary<NSString *, id> *)views
                     identifier:(nonnull NSString *)identifier;

Swift

class func constraints(withVisualFormat format: String, options opts: NSLayoutConstraint.FormatOptions = [], metrics: [String : Any]?, views: [String : Any]?, identifier: String) -> [NSLayoutConstraint]