UPGRADE YOUR SKILLS: Learn advanced Swift and SwiftUI on Hacking with Swift+! >>

How to create custom colors using UIColor RGB and hues

Swift version: 5.6

Paul Hudson    @twostraws   

Although there are quite a few built-in UIColors, you'll want to create your own very frequently. This can be done in a number of ways, but the most common is specifying individual values for red, green, blue and alpha, like this:

let col1 = UIColor(red: 1, green: 0, blue: 0, alpha: 1)

Each of those numbers need to be between 0 and 1.

An alternative way is to specify color values as hue, saturation and brightness, or HSB. Hue is a value between 0 and 1 on a color wheel, where 0 and 1 are both red. Saturation is how deep the color should be (so 0 is just gray) and brightness is how light the shade should be.

Here's how it's done:

let col2 = UIColor(hue: 0, saturation: 0.66, brightness: 0.66, alpha: 1)
let col3 = UIColor(hue: 0.25, saturation: 0.66, brightness: 0.66, alpha: 1)
let col4 = UIColor(hue: 0.5, saturation: 0.66, brightness: 0.66, alpha: 1)
let col5 = UIColor(hue: 0.75, saturation: 0.66, brightness: 0.66, alpha: 1)

The advantage to using HSB rather than RGB is that you can generate very similar colors by keeping the saturation and brightness constant and changing only the hue – the code above generates some nice pastel shades of red, green, cyan and magenta, for example.

Hacking with Swift is sponsored by RevenueCat

SPONSORED Take the pain out of configuring and testing your paywalls. RevenueCat's Paywalls allow you to remotely configure your entire paywall view without any code changes or app updates.

Learn more here

Sponsor Hacking with Swift and reach the world's largest Swift community!

Available from iOS 2.0

Similar solutions…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

BUY OUR BOOKS
Buy Pro Swift Buy Pro SwiftUI Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let us know!

Average rating: 3.6/5

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.