---
title: Action Identifiers
framework: quartzcore
role: collectionGroup
role_heading: API Collection
path: quartzcore/action-identifiers
---

# Action Identifiers

These constants are the predefined action identifiers used by action(forKey:), add(_:forKey:), defaultAction(forKey:), removeAnimation(forKey:), Layer Filters, and the CAAction protocol method run(forKey:object:arguments:).

## Topics

### Constants

- [kCAOnOrderIn](quartzcore/kcaonorderin.md)
- [kCAOnOrderOut](quartzcore/kcaonorderout.md)
- [kCATransition](quartzcore/kcatransition.md)

## See Also

### Constants

- [CAAutoresizingMask](quartzcore/caautoresizingmask.md)
- [CAEdgeAntialiasingMask](quartzcore/caedgeantialiasingmask.md)
- [Identity Transform](quartzcore/identity-transform.md)
- [Scaling Filters](quartzcore/scaling-filters.md)
- [CATransform3D](quartzcore/catransform3d.md)
- [CALayer.DynamicRange](quartzcore/calayer/dynamicrange.md)