Swift Extensions

Extensions.swift

//
//  Extensions.swift
//
//  Created by Valentin Kalchev on 17/11/2015.
//  Copyright © 2015 Valentin Kalchev. All rights reserved.
//

import Foundation

extension Array {
    
    // Shuffle the order of an array's elements.
    mutating func shuffle() {
        for _ in 0..<self.count {
            sortInPlace {
                (_,_) in arc4random() < arc4random()
            }
        }
    }
    
    func sum() -> Int {
        var sum = 0
        
        for (_, obj) in self.enumerate() {
            sum += obj as! Int
        }
        
        return sum
    }
}

extension UIColor {

    // Init UIColor with hex value and alpha
    convenience init(hex: Int, alpha: CGFloat = 1.0) {
        let r = CGFloat((hex & 0xFF0000) >> 16) / 255.0
        let g = CGFloat((hex & 0x00FF00) >> 08) / 255.0
        let b = CGFloat((hex & 0x0000FF) >> 00) / 255.0
        self.init(red:r, green:g, blue:b, alpha:alpha)
    }
}

// Zoom to point on UIScrollView
extension UIScrollView {
    func zoomToPoint(var zoomPoint: CGPoint, withScale scale: CGFloat, animated: Bool) {
        
        var contentSize = CGSize()
        contentSize.width = (self.contentSize.width / self.zoomScale)
        contentSize.height = (self.contentSize.height / self.zoomScale)
        
        print("Content size: \(contentSize)")
        //translate the zoom point to relative to the content rect
        zoomPoint.x = (zoomPoint.x / self.bounds.size.width) * contentSize.width
        zoomPoint.y = (zoomPoint.y / self.bounds.size.height) * contentSize.height
        
        //derive the size of the region to zoom to
        var  zoomSize = CGSize()
        zoomSize.width = self.bounds.size.width / scale
        zoomSize.height = self.bounds.size.height / scale
        
        //offset the zoom rect so the actual zoom point is in the middle of the rectangle
        var  zoomRect = CGRect()
        zoomRect.origin.x = zoomPoint.x - zoomSize.width / 2.0
        zoomRect.origin.y = zoomPoint.y - zoomSize.height / 2.0
        zoomRect.size.width = zoomSize.width
        zoomRect.size.height = zoomSize.height
        
        self.zoomToRect(zoomRect, animated: animated)
    }
}

where sortInPlace defined?