# setColors:atLocations: Sets the colors and corresponding unit distance values to create gradients. iOS, iPadOS, Mac Catalyst, tvOS, visionOS, watchOS: ``` - (void) setColors:(NSArray *) colors atLocations:(NSArray *) locations; ``` macOS: ``` - (void) setColors:(NSArray *) colors atLocations:(NSArray *) locations; ``` ## Parameters `colors` An array of colors making up the transition points of the gradient. `locations` An array of unit distance values that correspond to the provided colors. ## Discussion The unit distance value of `0` represents the start of the polyline, and `1` represents the end of the polyline. A gradient may have any number of steps along the length of the polyline. To determine a location along the polyline, use [`location(atPointIndex:)`](/documentation/MapKit/MKMultiPoint/location(atPointIndex:)), or retrieve a set of locations using [`locationsAtPointIndexes:`](/documentation/MapKit/MKMultiPoint/locationsAtPointIndexes:). --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)