Early Swift version of CSRevealingViewController (Two VCs, one gist)

SwipeUpViewControllerDemo

//
//  BottomViewController.swift
//  SwipeUpViewControllerDemo
//
//  Created by Lange, Josef on 7/14/14.
//

import UIKit

class BottomViewController: UIViewController {

    var bottomSpaceConstraint : NSLayoutConstraint?
    @IBOutlet var containerView : UIView
    
    init(coder aDecoder: NSCoder!)  {
        super.init(coder: aDecoder)
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        let bindings = ["containerView": self.containerView]
        self.bottomSpaceConstraint = NSLayoutConstraint.constraintsWithVisualFormat("V:[containerView]-0-|", options: nil, metrics: nil, views: bindings)[0] as? NSLayoutConstraint
        self.view.addConstraint(self.bottomSpaceConstraint)
        self.view.layoutIfNeeded()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    override func willRotateToInterfaceOrientation(toInterfaceOrientation: UIInterfaceOrientation, duration: NSTimeInterval) {
        // "Best guess" what our slideup constrain should be.
        if(self.bottomSpaceConstraint?.constant > 0.0) {
            self.reveal("UP", animated: false, flip: true)
        } else if(self.bottomSpaceConstraint?.constant < 0.0) {
            self.reveal("DOWN", animated: false, flip: true)
        }
    }
    
    override func didRotateFromInterfaceOrientation(toInterfaceOrientation: UIInterfaceOrientation) {
        if(self.bottomSpaceConstraint?.constant > 0.0) {
            self.reveal("UP", animated: false)
        } else if(self.bottomSpaceConstraint?.constant < 0.0) {
            self.restoreTopView()
        }
    }
    
    func reveal(translation : Float) {
        println(translation)
        let translation = translation * -1.0
        let strong = self.bottomSpaceConstraint as NSLayoutConstraint
        if (0 < translation) {
            strong.constant = translation
            self.view.layoutIfNeeded()

        }
    }
    
    func reveal(direction: NSString, animated: Bool, flip: Bool = false) {
        var changeFlag = 1.0 as Float
        if direction == "UP" {
            changeFlag = 1.0 as Float
        } else if direction == "DOWN" {
            changeFlag = -1.0 as Float
        }
        
        var constant = flip ? self.view.frame.size.width : self.view.frame.size.height
        var newBottomSpace = changeFlag * constant as Float - 100.0
        
        if(animated == true) {
            UIView.animateWithDuration(0.2, animations: {
                let strong = self.bottomSpaceConstraint as NSLayoutConstraint
                strong.constant = newBottomSpace
                self.view.layoutIfNeeded()
                }, completion: {
                    _ in
                    return
                })
        } else {
            let strong = self.bottomSpaceConstraint as NSLayoutConstraint
            strong.constant = newBottomSpace
            self.view.layoutIfNeeded()
        }
    }
    
    @IBAction func restoreTopView() {
        UIView.animateWithDuration(0.05, animations: {
                let strong = self.bottomSpaceConstraint as NSLayoutConstraint
                strong.constant = 0.0
                self.view.layoutIfNeeded()
            }, completion: {
                _ in
                return
            })
    }


}



//
//  TopViewController.swift
//  SwipeUpViewControllerDemo
//
//  Created by Lange, Josef on 7/14/14.
//

import UIKit

class TopViewController: UIViewController, UIGestureRecognizerDelegate {
    
    init(coder aDecoder: NSCoder!)  {
        super.init(coder: aDecoder)
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        var panRecognizer = UIPanGestureRecognizer(target: self, action: "respondToPan:")
        self.view.addGestureRecognizer(panRecognizer)
        // Do any additional setup after loading the view.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    func respondToPan(recognizer: UIPanGestureRecognizer) {
        let translationInView = recognizer.translationInView(self.view).y
        if(recognizer.state == UIGestureRecognizerState.Ended) {
            var verticalVelocity = recognizer.velocityInView(self.view).y
            if(abs(verticalVelocity) > 100.0) {
                if(verticalVelocity > 0.0) {
                    self.returnView()
                } else {
                    self.reveal("UP", animated: false)
                }
            }
        } else {
            self.moveMyView(translationInView)
        }
    }
    
    func returnView() {
        let below = self.parentViewController as BottomViewController
        below.restoreTopView()
    }
    
    func moveMyView(translationInView: Float) {
        let below = self.parentViewController as BottomViewController
        below.reveal(translationInView)
    }
    
    func reveal(direction : NSString, animated: Bool) {
        let below = self.parentViewController as BottomViewController
        below.reveal(direction, animated: animated)
    }
    
    @IBAction func revealBelow(sender : UIControl) {
        self.reveal("UP", animated: true)
    }

}