UIColor initializer from Hex number, in swift.

UIColor+Hex.swift

import UIKit

public extension UIColor
{
    class func components(alphaHex hex : UInt32) -> (r:UInt8, g:UInt8, b:UInt8, a:UInt8)
    {
        let r = UInt8((hex & 0xFF000000) >> 24)
        let g = UInt8((hex & 0x00FF0000) >> 16)
        let b = UInt8((hex & 0x0000FF00) >> 8)
        let a = UInt8((hex & 0x000000FF))
        
        return (r,g,b,a)
    }
    
    /// Creates a UIColor from a 0xRRGGBBAA value
    convenience init(alphaHex hex : UInt32)
    {
        let (r,g,b,a) = UIColor.components(alphaHex: hex)
        self.init(red: CGFloat(r) / 255.0, green: CGFloat(g) / 255.0, blue: CGFloat(b) / 255.0, alpha: CGFloat(a) / 255.0)
    }
    
    /// Creates a UIColor from a right-padded UInt32 (0x00RRGGBB or 0xRRGGBB), with optional alpha
    convenience init(hex : UInt32, alpha : CGFloat = 1.0)
    {
        let (r,g,b,_) = UIColor.components(alphaHex: hex << 8)
        self.init(red: CGFloat(r) / 255.0, green: CGFloat(g) / 255.0, blue: CGFloat(b) / 255.0, alpha: alpha)
    }
}