---
title: NSLayoutConstraint.Attribute
framework: uikit
role: symbol
role_heading: Enumeration
path: uikit/nslayoutconstraint/attribute
---

# NSLayoutConstraint.Attribute

The part of the object’s visual representation that should be used to get the value for the constraint.

## Declaration

```swift
enum Attribute
```

## Topics

### Constants

- [NSLayoutConstraint.Attribute.left](uikit/nslayoutconstraint/attribute/left.md)
- [NSLayoutConstraint.Attribute.right](uikit/nslayoutconstraint/attribute/right.md)
- [NSLayoutConstraint.Attribute.top](uikit/nslayoutconstraint/attribute/top.md)
- [NSLayoutConstraint.Attribute.bottom](uikit/nslayoutconstraint/attribute/bottom.md)
- [NSLayoutConstraint.Attribute.leading](uikit/nslayoutconstraint/attribute/leading.md)
- [NSLayoutConstraint.Attribute.trailing](uikit/nslayoutconstraint/attribute/trailing.md)
- [NSLayoutConstraint.Attribute.width](uikit/nslayoutconstraint/attribute/width.md)
- [NSLayoutConstraint.Attribute.height](uikit/nslayoutconstraint/attribute/height.md)
- [NSLayoutConstraint.Attribute.centerX](uikit/nslayoutconstraint/attribute/centerx.md)
- [NSLayoutConstraint.Attribute.centerY](uikit/nslayoutconstraint/attribute/centery.md)
- [NSLayoutConstraint.Attribute.lastBaseline](uikit/nslayoutconstraint/attribute/lastbaseline.md)
- [NSLayoutConstraint.Attribute.firstBaseline](uikit/nslayoutconstraint/attribute/firstbaseline.md)
- [NSLayoutConstraint.Attribute.leftMargin](uikit/nslayoutconstraint/attribute/leftmargin.md)
- [NSLayoutConstraint.Attribute.rightMargin](uikit/nslayoutconstraint/attribute/rightmargin.md)
- [NSLayoutConstraint.Attribute.topMargin](uikit/nslayoutconstraint/attribute/topmargin.md)
- [NSLayoutConstraint.Attribute.bottomMargin](uikit/nslayoutconstraint/attribute/bottommargin.md)
- [NSLayoutConstraint.Attribute.leadingMargin](uikit/nslayoutconstraint/attribute/leadingmargin.md)
- [NSLayoutConstraint.Attribute.trailingMargin](uikit/nslayoutconstraint/attribute/trailingmargin.md)
- [NSLayoutConstraint.Attribute.centerXWithinMargins](uikit/nslayoutconstraint/attribute/centerxwithinmargins.md)
- [NSLayoutConstraint.Attribute.centerYWithinMargins](uikit/nslayoutconstraint/attribute/centerywithinmargins.md)
- [NSLayoutConstraint.Attribute.notAnAttribute](uikit/nslayoutconstraint/attribute/notanattribute.md)

### Initializers

- [init(rawValue:)](uikit/nslayoutconstraint/attribute/init(rawvalue:).md)

## Relationships

### Conforms To

- [BitwiseCopyable](swift/bitwisecopyable.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [RawRepresentable](swift/rawrepresentable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Constants

- [NSLayoutConstraint.Relation](uikit/nslayoutconstraint/relation-swift.enum.md)
- [NSLayoutConstraint.FormatOptions](uikit/nslayoutconstraint/formatoptions.md)
- [NSLayoutConstraint.Orientation](appkit/nslayoutconstraint/orientation.md)
- [NSLayoutConstraint.Axis](uikit/nslayoutconstraint/axis.md)
- [NSEdgeInsets](foundation/nsedgeinsets.md)
- [NSLAYOUTCONSTRAINT_H](uikit/nslayoutconstraint_h.md)