Swift version: 5.2
Since Xcode 9.0 we’ve been able to create named colors directly inside asset catalogs, which means it’s possible to select a precise color once then use it uniformly across all code and storyboards.
To try this out, open your asset catalog, click the + button, then choose New Color Set from the menu that appears. Select the new color that got created – it will be a large white square – then press Alt+Cmd+4 to activate the attributes inspector so that you can customize it.
Named colors are comprised of two rather obvious parts: a name (e.g. “PayPal blue”) and a color, which you can specify as ranges from 0-1, ranges from 0-255, or hexadecimal.
Once a named color is in place you can use it code like this:
myView.backgroundColor = UIColor(named: "Chartreuse")
You can also use it inside storyboards by selecting it from the color dropdown menu – all your named colors will automatically be shown in their own section of the menu.
Available from iOS 11.0
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
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