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# MTKViewDelegate

Methods for responding to a MetalKit view’s drawing and resizing events.

```
protocol MTKViewDelegate : NSObjectProtocol
```

## Overview

You can set an object that implements the [`MTKViewDelegate`](/documentation/MetalKit/MTKViewDelegate) protocol as a [`MTKView`](/documentation/MetalKit/MTKView) object’s delegate. Use a delegate to provide a drawing method to a [`MTKView`](/documentation/MetalKit/MTKView) object and respond to rendering events without subclassing the [`MTKView`](/documentation/MetalKit/MTKView) class.

## Topics

### Changing the View’s Layout

[`mtkView(_:drawableSizeWillChange:)`](/documentation/MetalKit/MTKViewDelegate/mtkView(_:drawableSizeWillChange:))

Updates the view’s contents upon receiving a change in layout, resolution, or size.

### Drawing the View’s Contents

[`draw(in:)`](/documentation/MetalKit/MTKViewDelegate/draw(in:))

Draws the view’s contents.


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