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# NSImageDelegate

A set of optional methods that you can use to respond to drawing failures and manage incremental loads.

```
protocol NSImageDelegate : NSObjectProtocol
```

## Topics

### Responding to Drawing Failure

[`imageDidNotDraw(_:in:)`](/documentation/AppKit/NSImageDelegate/imageDidNotDraw(_:in:))

Tells the delegate that the image object is unable, for whatever reason, to lock focus on its image or draw in the specified rectangle.

### Managing Incremental Loads

[`image:didLoadPartOfRepresentation:withValidRows:`](/documentation/AppKit/NSImageDelegate/image:didLoadPartOfRepresentation:withValidRows:)

Tells the delegate that part of the incrementally loaded image data is available.

[`image:didLoadRepresentation:withStatus:`](/documentation/AppKit/NSImageDelegate/image:didLoadRepresentation:withStatus:)

Tells the delegate that an incrementally loaded image has been loaded and decompressed as completely as is possible.

[`image:didLoadRepresentationHeader:`](/documentation/AppKit/NSImageDelegate/image:didLoadRepresentationHeader:)

Tells the delegate that enough data has been read to determine the size of the image.

[`image:willLoadRepresentation:`](/documentation/AppKit/NSImageDelegate/image:willLoadRepresentation:)

Tells the delegate that the image object is about to access its underlying bitmap data.

[`NSImage.LoadStatus`](/documentation/AppKit/NSImage/LoadStatus)

Status values for incremental image loading.


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