Protocol

CALayerDelegate

Methods your app can implement to respond to layer-related events.

Declaration

@protocol CALayerDelegate

Overview

You can implement the methods of this protocol to provide the layer’s content, handle the layout of sublayers, and provide custom animation actions to perform. The object that implements this protocol must be assigned to the delegate property of the layer object.

Topics

Providing the Layer's Content

- displayLayer:

Tells the delegate to implement the display process.

- drawLayer:inContext:

Tells the delegate to implement the display process using the layer's CGContextRef.

- layerWillDraw:

Notifies the delegate of an imminent draw.

Laying Out Sublayers

- layoutSublayersOfLayer:

Tells the delegate a layer's bounds have changed.

Providing a Layer's Actions

- actionForLayer:forKey:

Returns the default action of the actionForKey: method.

Relationships

Inherits From

Conforming Types

See Also

Layer Basics

CALayer

An object that manages image-based content and allows you to perform animations on that content.

CAConstraint

A representation of a single layout constraint between two layers.

CALayoutManager

Methods that allow an object to manage the layout of a layer and its sublayers.

CAConstraintLayoutManager

An object that provides a constraint-based layout manager.

CAAction

An interface that allows objects to respond to actions triggered by a CALayer change.

Beta Software

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