How to compare a color in swift

Question

I am trying to compare colors but I cannot use the isEqual method because I am trying to compare the color of the background of a UICollectionViewCell.

What is the correct way to compare colors in this situation?

if(cell!.layer.backgroundColor! == UIColor.redColor().CGColor)
{
    cell?.layer.backgroundColor = UIColor.redColor().CGColor
}

I'm sorry if I'm missing something but you can use cell.backgroundColor and compare it to another UIColor. I've come across this in some fast research if you're working only with CGColors, http://stackoverflow.com/a/8191171/4096655 — Fred Faust, Apr 14 '16 at 02:43

score 12 · Accepted Answer · answered Apr 14 '16 at 02:47

12

Try CGColorEqualToColor(_ color1: CGColor!, _ color2: CGColor!) -> Bool.

answered Apr 14 '16 at 02:47

Inhan

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CGColorEqualToColor is deprecated in swift3 – Den Jun 17 '17 at 23:43

Leo Dabus · Answer 2 · 2021-09-06T13:58:12.517

Swift 3 or later

CGColorEqualToColor is deprecated. You can now directly check them for equality:

let color1 = UIColor(hue: 0, saturation: 1, brightness: 1, alpha: 1).cgColor
let color2 = UIColor.red.cgColor

print(color1 == color2)   // "true\n"

Original post

extension CGColor: Equatable { }
public func ==(lhs: CGColor, rhs: CGColor) -> Bool {
    return CGColorEqualToColor(lhs,rhs)
}
let color1 = UIColor(hue: 0, saturation: 1, brightness: 1, alpha: 1).CGColor
let color2 = UIColor.redColor().CGColor

print(color1 == color2)   // "true\n"

score 3 · Answer 3 · answered Apr 14 '16 at 02:57

I've come up with this in a playground, I've assigned the backgroundColor property of the UICollectionViewCell with a UIColor and then created a UIColor from it's layer.backgroundColor CGColor property:

let blue = UIColor.blueColor()

let collectionCell = UICollectionViewCell()

collectionCell.backgroundColor = blue

let cellLayerBgrndColor = UIColor(CGColor: collectionCell.layer.backgroundColor!)

if blue == cellLayerBgrndColor {

print("equal") // Prints equal
}

score 2 · Answer 4 · answered Aug 21 '17 at 10:34

You could compare the strings produced by calling the .description property like:

// UIColor.red.description -> "UIExtendedSRGBColorSpace 1 0 0 1"
if(cell!.layer.backgroundColor!.description == UIColor.red.description)
{
    cell?.layer.backgroundColor = UIColor.redColor().CGColor
}

But note that colorspace must also match.

Next Developer · Answer 5 · 2017-08-30T07:46:42.547

0

In Swift 3 you can simply compare the colors with ===

let c1 = UIColor.red.cgColor
let c2 = UIColor.red.cgColor

if c1 === c2 {
   print('Equal')
}

edited Aug 30 '17 at 07:46

answered Aug 30 '17 at 07:20

Next Developer

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This is completely wrong except possibly for some preset colors. – Rudedog Apr 27 '22 at 15:24

score 0 · Answer 6 · answered Apr 27 '22 at 13:39

0

Instead of CGColorEqualToColor(_ color1: CGColor!, _ color2: CGColor!) -> Bool need to use if color1.cgColor == UIColor.systemBlue.cgColor { } which returns Bool.

answered Apr 27 '22 at 13:39

Dayanithi Natarajan

833
12
21

How to compare a color in swift

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