Check out example codes for "uicolor gray". It will help you in understanding the concepts better.

Code Example 1

// you can use digital color picker app available in mac os,
//Then whichever component's color you want just hover mouse pointer there and you will get the RGB Values in digital color meter and that RGB values you can use in setting the background of your view,
//in this way,
UIColor.init(red: 49.0/255.0, green: 49.0/255.0, blue: 49.0/255.0, alpha: 1.0)

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