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QuartzCore Framework Reference CAConstraintLayoutManager Class Reference

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CAConstraintLayoutManager

Inheritance


Conforms To


Import Statement


Swift

import QuartzCore

Objective-C

@import QuartzCore;

Availability


Available in OS X v10.5 and later.

The CAConstraintLayoutManager class provides a constraint-based layout manager. You use the shared instance of this object by assigning it to the layoutManager property of any layer objects to which you have added constraints. During a layout update, Core Animation uses the layout manager to update the size and position of the sublayers based on the registered set of constraints.

Constraints let you define a set of geometric relationships between a layer and its sibling layers or between a layer and its superlayer. These relationships are expressed using constraint objects, which are instances of the CAConstraint class. When creating constraints, you can reference a layer by name using that object’s name property. You can also use the special name superlayer to refer to the layer's superlayer.

This class is not meant to be subclassed.

  • Returns the shared layout manager object.

    Declaration

    Swift

    class func layoutManager() -> AnyObject!

    Objective-C

    + (id)layoutManager

    Return Value

    The shared layout manager object.

    Discussion

    You can assign the returned object to any layers that manage layout using constraints.

    Import Statement

    Objective-C

    @import QuartzCore;

    Swift

    import QuartzCore

    Availability

    Available in OS X v10.5 and later.