ios - Making RGB color in Xcode

Question

I am using RGB values of a color from Photoshop and using the same in Xcode the values are.Color-R-160,G-97,B-5...the color in Photoshop appears yellowish but in Xcode when I used

myLabel.textColor = [UIColor colorWithRed:160 green:97 blue:5 alpha:1] ;

the color appears whitish.

Why this difference is happening?

Answer 1

Objective-C

You have to give the values between 0 and 1.0. So divide the RGB values by 255.

myLabel.textColor= [UIColor colorWithRed:(160/255.0) green:(97/255.0) blue:(5/255.0) alpha:1] ;

Update:

You can also use this macro

#define Rgb2UIColor(r, g, b)  [UIColor colorWithRed:((r) / 255.0) green:((g) / 255.0) blue:((b) / 255.0) alpha:1.0]

and you can call in any of your class like this

 myLabel.textColor = Rgb2UIColor(160, 97, 5);

Swift

This is the normal color synax

myLabel.textColor = UIColor(red: (160/255.0), green: (97/255.0), blue: (5/255.0), alpha: 1.0) 
//The values should be between 0 to 1

Swift is not much friendly with macros

Complex macros are used in C and Objective-C but have no counterpart in Swift. Complex macros are macros that do not define constants, including parenthesized, function-like macros. You use complex macros in C and Objective-C to avoid type-checking constraints or to avoid retyping large amounts of boilerplate code. However, macros can make debugging and refactoring difficult. In Swift, you can use functions and generics to achieve the same results without any compromises. Therefore, the complex macros that are in C and Objective-C source files are not made available to your Swift code.

So we use extension for this

extension UIColor {
    convenience init(_ r: Double,_ g: Double,_ b: Double,_ a: Double) {
        self.init(red: r/255, green: g/255, blue: b/255, alpha: a)
    }
}

You can use it like

myLabel.textColor = UIColor(160.0, 97.0, 5.0, 1.0)