Slide Segue in Swift - ios

Question

I'm trying to create a horizontally sliding segue that'll pan from one view to the next. I have the panning down, but it shows a black space in the area being revealed where it should be showing the next view controller. This is how I'm implementing my segue
class SlideSegue: UIStoryboardSegue {
enum Direction {
case Left
case Right
}
// MARK: - Properties
var direction = Direction.Left
// MARK: -
override func perform() {
let srcVc = self.sourceViewController
let destVc = self.destinationViewController
let destView = destVc.view.snapshotViewAfterScreenUpdates(true)
var frame = destView.frame
frame.origin.x = CGFloat(valForDirection()) * srcVc.view.frame.width
destView.frame = frame
srcVc.view.addSubview(destView)
UIView.animateWithDuration(0.3, animations: { () -> Void in
let x = CGFloat(self.valForDirection()) * srcVc.view.bounds.width
let slide = CGAffineTransformMakeTranslation(x, 0)
srcVc.view.transform = slide
}) { (finished: Bool) -> Void in
srcVc.presentViewController(destVc, animated: false, completion: nil)
destView.removeFromSuperview()
}
}
func valForDirection() -> Int {
return direction == Direction.Left ? -1 : 1
}
}
class SlideLeftSegue: SlideSegue {
override func perform() {
self.direction = Direction.Left
super.perform()
}
}
class SlideRightSegue: SlideSegue {
override func perform() {
self.direction = Direction.Right
super.perform()
}
}
EDIT
EDIT (SOLVED)
This is the final working solution thanks the two answers below
class SlideSegue: UIStoryboardSegue {
enum Direction: Int {
case Left = 1
case Right = -1
}
// MARK: - Properties
var direction = Direction.Left
// MARK: -
override func perform() {
let srcVc = self.sourceViewController
let destVc = self.destinationViewController
let destView = destVc.view.snapshotViewAfterScreenUpdates(true)
var frame = destView.frame
frame.origin.x = CGFloat(direction.rawValue) * srcVc.view.frame.width
destView.frame = frame
srcVc.view.addSubview(destView)
UIView.animateWithDuration(0.3, animations: { () -> Void in
let x = -CGFloat(self.direction.rawValue) * srcVc.view.bounds.width
let slide = CGAffineTransformMakeTranslation(x, 0)
srcVc.view.transform = slide
}) { (finished: Bool) -> Void in
srcVc.presentViewController(destVc, animated: false, completion: nil)
destView.removeFromSuperview()
}
}
}
class SlideLeftSegue: SlideSegue {
override func perform() {
self.direction = Direction.Left
super.perform()
}
}
class SlideRightSegue: SlideSegue {
override func perform() {
self.direction = Direction.Right
super.perform()
}
}

Answer 1

I test with the following modification, and it work well.
func valForDirection() -> Int {
return direction == Direction.Left ? 1 : -1
}
If sliding to left, the destView's originX should be it's width. else -width.

Answer 2

Try changing your SlideSegue class to this, removing the valForDirection function (I have taken the liberty to refactor it a little, if you don't mind)
class FirstCustomSegue: UIStoryboardSegue {
enum Direction: Int {
case Left = 1
case Right = -1
}
// MARK: - Properties
var direction = Direction.Left
// MARK: - Perform
override func perform() {
let srcVc = self.sourceViewController
let destVc = self.destinationViewController
destVc.view.frame = srcVc.view.frame
destVc.view.frame.origin.x = CGFloat(direction.rawValue) * srcVc.view.frame.width
let window = UIApplication.sharedApplication().keyWindow
window?.insertSubview(destVc.view, aboveSubview: srcVc.view)
UIView.animateWithDuration(0.3, animations: { () -> Void in
let x = CGFloat(self.direction.rawValue) * srcVc.view.bounds.width
destVc.view.frame.origin.x = 0
srcVc.view.frame.origin.x = -x
}) { (finished: Bool) -> Void in
srcVc.presentViewController(destVc, animated: false, completion: nil)
}
}
}
I haven't tested this yet, so I'm not 100% sure that the syntax is correct.
UPDATE: MatthewLuiHK seems to be right. All you have to do is flip around the values.
Credits: http://www.appcoda.com/custom-segue-animations/

Answer 3

This code works for me, it reveals the new view controller from beneath the VC being swiped away, however when the segue is complete the view controller briefly flashes black.
Any ideas how to ensure a smooth transition every time?
import UIKit
class SlideSegue: UIStoryboardSegue {
enum Direction: Int {
case Left = 1
case Right = -1
}
// MARK: - Properties
var direction = Direction.Left
// MARK: -
override func perform() {
let srcVc = self.sourceViewController
let destVc = self.destinationViewController
let destView = destVc.view.snapshotViewAfterScreenUpdates(true)
var frame = destView.frame
frame.origin.x = CGFloat(direction.rawValue) * srcVc.view.frame.width
destView.frame = frame
srcVc.view.addSubview(destView)
UIView.animateWithDuration(0.3, animations: { () -> Void in
let x = -CGFloat(self.direction.rawValue) * srcVc.view.bounds.width
let slide = CGAffineTransformMakeTranslation(x, 0)
srcVc.view.transform = slide
}) { (finished: Bool) -> Void in
srcVc.presentViewController(destVc, animated: false, completion: nil)
destView.removeFromSuperview()
}
}
}
class SlideLeftSegue: SlideSegue {
override func perform() {
self.direction = Direction.Left
super.perform()
}
}
class SlideRightSegue: SlideSegue {
override func perform() {
self.direction = Direction.Right
super.perform()
}
}
Many thanks