Question

我正在使用Swiftpages。当应用程序打开时，它看起来像第一张图片。 enter image description here

但应用程序转到后台并在设备上打开了不同的应用程序，再次打开我的应用程序后它看起来像第二张图片。 enter image description here

我更新到Swift 3，但我无法弄清楚问题，我在Github上写了这个问题，但没有回复。

public class SwiftPages: UIView {
private lazy var token = 0

var containerVieww: UIView!
private var scrollView: UIScrollView!
private var topBar: UIView!
var animatedBar: UIView!
var viewControllerIDs = [String]()
private var buttonTitles = [String]()
private var buttonImages = [UIImage]()
private var pageViews = [UIViewController?]()
private var currentPage: Int = 0

// Container view position variables
private var xOrigin: CGFloat = 0
private var yOrigin: CGFloat = 64
private var distanceToBottom: CGFloat = 0

// Color variables
private var animatedBarColor = UIColor(red: 28/255, green: 95/255, blue: 185/255, alpha: 1)
private var topBarBackground = UIColor.white
private var buttonsTextColor = UIColor.gray
private var containerViewBackground = UIColor.white

// Item size variables
private var topBarHeight: CGFloat = 52
private var animatedBarHeight: CGFloat = 3

// Bar item variables
private var aeroEffectInTopBar = false //This gives the top bap a blurred effect, also overlayes the it over the VC's
private var buttonsWithImages = false
var barShadow = true
private var shadowView : UIView!
private var shadowViewGradient = CAGradientLayer()
private var buttonsTextFontAndSize = UIFont(name: "HelveticaNeue-Light", size: 20)!
private var blurView : UIVisualEffectView!
private var barButtons = [UIButton?]()

// MARK: - Positions Of The Container View API -
public func setOriginX (origin : CGFloat) { xOrigin = origin }
public func setOriginY (origin : CGFloat) { yOrigin = origin }
public func setDistanceToBottom (distance : CGFloat) { distanceToBottom = distance }

// MARK: - API's -
public func setAnimatedBarColor (color : UIColor) { animatedBarColor = color }
public func setTopBarBackground (color : UIColor) { topBarBackground = color }
public func setButtonsTextColor (color : UIColor) { buttonsTextColor = color }
public func setContainerViewBackground (color : UIColor) { containerViewBackground = color }
public func setTopBarHeight (pointSize : CGFloat) { topBarHeight = pointSize}
public func setAnimatedBarHeight (pointSize : CGFloat) { animatedBarHeight = pointSize}
public func setButtonsTextFontAndSize (fontAndSize : UIFont) { buttonsTextFontAndSize = fontAndSize}
public func enableAeroEffectInTopBar (boolValue : Bool) { aeroEffectInTopBar = boolValue}
public func enableButtonsWithImages (boolValue : Bool) { buttonsWithImages = boolValue}
public func enableBarShadow (boolValue : Bool) { barShadow = boolValue}

override public func draw(_ rect: CGRect) {
    DispatchQueue.main.async {

        let pagesContainerHeight = self.frame.height - self.yOrigin - self.distanceToBottom
        let pagesContainerWidth = self.frame.width

        // Set the notifications for an orientation change & BG mode
        let defaultNotificationCenter = NotificationCenter.default
        defaultNotificationCenter.addObserver(self, selector: #selector(SwiftPages.applicationWillEnterBackground), name: NSNotification.Name.UIApplicationWillResignActive, object: nil)
        defaultNotificationCenter.addObserver(self, selector: #selector(SwiftPages.orientationWillChange), name: NSNotification.Name.UIApplicationWillChangeStatusBarOrientation, object: nil)
        defaultNotificationCenter.addObserver(self, selector: #selector(SwiftPages.orientationDidChange), name: NSNotification.Name.UIDeviceOrientationDidChange, object: nil)
        defaultNotificationCenter.addObserver(self, selector: #selector(SwiftPages.applicationWillEnterForeground), name: NSNotification.Name.UIApplicationDidBecomeActive, object: nil)



        // Set the containerView, every item is constructed relative to this view
        self.containerVieww = UIView(frame: CGRect(x: self.xOrigin, y: self.yOrigin, width: pagesContainerWidth, height: pagesContainerHeight))
        self.containerVieww.backgroundColor = self.containerViewBackground
        self.containerVieww.translatesAutoresizingMaskIntoConstraints = false
        self.addSubview(self.containerVieww)

        //Add the constraints to the containerView.
        if #available(iOS 9.0, *) {
            let horizontalConstraint = self.containerVieww.centerXAnchor.constraint(equalTo: self.centerXAnchor)
            let verticalConstraint = self.containerVieww.centerYAnchor.constraint(equalTo: self.centerYAnchor)
            let widthConstraint = self.containerVieww.widthAnchor.constraint(equalTo: self.widthAnchor)
            let heightConstraint = self.containerVieww.heightAnchor.constraint(equalTo: self.heightAnchor)
            NSLayoutConstraint.activate([horizontalConstraint, verticalConstraint, widthConstraint, heightConstraint])
        }


        // Set the scrollview
        if self.aeroEffectInTopBar {
            self.scrollView = UIScrollView(frame: CGRect(x: 0, y: 0, width: self.containerVieww.frame.size.width, height: self.containerVieww.frame.size.height))
        } else {
            self.scrollView = UIScrollView(frame: CGRect(x: 0, y: self.topBarHeight, width: self.containerVieww.frame.size.width, height: self.containerVieww.frame.size.height - self.topBarHeight))
        }
        self.scrollView.isPagingEnabled = true
        self.scrollView.showsHorizontalScrollIndicator = false
        self.scrollView.showsVerticalScrollIndicator = false
        self.scrollView.delegate = self
        self.scrollView.backgroundColor = UIColor.clear
        self.scrollView.contentOffset = CGPoint(x: 0, y: 0)
        self.scrollView.translatesAutoresizingMaskIntoConstraints = false
        self.scrollView.isScrollEnabled = false
        self.containerVieww.addSubview(self.scrollView)

        // Add the constraints to the scrollview.
        if #available(iOS 9.0, *) {
            let leadingConstraint = self.scrollView.leadingAnchor.constraint(equalTo: self.containerVieww.leadingAnchor)
            let trailingConstraint = self.scrollView.trailingAnchor.constraint(equalTo: self.containerVieww.trailingAnchor)
            let topConstraint = self.scrollView.topAnchor.constraint(equalTo: self.containerVieww.topAnchor)
            let bottomConstraint = self.scrollView.bottomAnchor.constraint(equalTo: self.containerVieww.bottomAnchor)
            NSLayoutConstraint.activate([leadingConstraint, trailingConstraint, topConstraint, bottomConstraint])
        }

        // Set the top bar
        self.topBar = UIView(frame: CGRect(x: 0, y: 0, width: self.containerVieww.frame.size.width, height: self.topBarHeight))
        self.topBar.backgroundColor = self.topBarBackground

        if self.aeroEffectInTopBar {
            // Create the blurred visual effect
            // You can choose between ExtraLight, Light and Dark
            self.topBar.backgroundColor = UIColor.clear

            let blurEffect: UIBlurEffect = UIBlurEffect(style: .light)
            self.blurView = UIVisualEffectView(effect: blurEffect)

            self.blurView.frame = self.topBar.bounds
            self.blurView.translatesAutoresizingMaskIntoConstraints = false
            self.topBar.addSubview(self.blurView)
        }

        self.topBar.translatesAutoresizingMaskIntoConstraints = false
        self.containerVieww.addSubview(self.topBar)

        // Set the top bar buttons
        // Check to see if the top bar will be created with images ot text
        if self.buttonsWithImages {
            var buttonsXPosition: CGFloat = 0

            for (index, image) in self.buttonImages.enumerated() {
                let frame = CGRect(x: buttonsXPosition, y: 0, width: self.containerVieww.frame.size.width / CGFloat(self.viewControllerIDs.count), height: self.topBarHeight)

                let barButton = UIButton(frame: frame)
                barButton.backgroundColor = UIColor.clear
                barButton.imageView?.contentMode = .scaleAspectFit
                barButton.setImage(image, for: .normal)
                barButton.tag = index
                barButton.addTarget(self, action: #selector(SwiftPages.barButtonAction), for: .touchUpInside)
                self.topBar.addSubview(barButton)
                self.barButtons.append(barButton)

                buttonsXPosition += self.containerVieww.frame.size.width / CGFloat(self.viewControllerIDs.count)
            }
        } else {
            var buttonsXPosition: CGFloat = 0

            for (index, title) in self.buttonTitles.enumerated() {
                let frame = CGRect(x: buttonsXPosition, y: 0, width: self.containerVieww.frame.size.width / CGFloat(self.viewControllerIDs.count), height: self.topBarHeight)

                let barButton = UIButton(frame: frame)
                barButton.backgroundColor = UIColor.clear
                barButton.titleLabel!.font = self.buttonsTextFontAndSize
                barButton.setTitle(title, for: .normal)
                barButton.setTitleColor(self.buttonsTextColor, for: .normal)
                barButton.tag = index
                barButton.addTarget(self, action: #selector(SwiftPages.barButtonAction), for: .touchUpInside)
                self.topBar.addSubview(barButton)
                self.barButtons.append(barButton)

                buttonsXPosition += self.containerVieww.frame.size.width / CGFloat(self.viewControllerIDs.count)
            }
        }

        // Set up the animated UIView
        self.animatedBar = UIView(frame: CGRect(x: 0, y: self.topBarHeight - self.animatedBarHeight + 1, width: (self.containerVieww.frame.size.width / CGFloat(self.viewControllerIDs.count)) * 0.8, height: self.animatedBarHeight))
        self.animatedBar.center.x = self.containerVieww.frame.size.width / CGFloat(self.viewControllerIDs.count << 1)
        self.animatedBar.backgroundColor = self.animatedBarColor
        self.containerVieww.addSubview(self.animatedBar)

        // Add the bar shadow (set to true or false with the barShadow var)
        if self.barShadow {
            self.shadowView = UIView(frame: CGRect(x: 0, y: self.topBarHeight, width: self.containerVieww.frame.size.width, height: 4))
            self.shadowViewGradient.frame = self.shadowView.bounds
            self.shadowViewGradient.colors = [UIColor(red: 150/255, green: 150/255, blue: 150/255, alpha: 0.28).cgColor, UIColor.clear.cgColor]
            self.shadowView.layer.insertSublayer(self.shadowViewGradient, at: 0)
            self.containerVieww.addSubview(self.shadowView)
        }

        let pageCount = self.viewControllerIDs.count

        // Fill the array containing the VC instances with nil objects as placeholders
        for _ in 0..<pageCount {
            self.pageViews.append(nil)
        }

        // Defining the content size of the scrollview
        let pagesScrollViewSize = self.scrollView.frame.size
        self.scrollView.contentSize = CGSize(width: pagesScrollViewSize.width * CGFloat(pageCount), height: pagesScrollViewSize.height)

        // Load the pages to show initially
        self.loadVisiblePages()

        // Do the initial alignment of the subViews
        self.alignSubviews()
    }
}

// MARK: - Initialization Functions -
public func initializeWithVCIDsArrayAndButtonTitlesArray (VCIDsArray: [String], buttonTitlesArray: [String]) {
    // Important - Titles Array must Have The Same Number Of Items As The viewControllerIDs Array
    if VCIDsArray.count == buttonTitlesArray.count {
        viewControllerIDs = VCIDsArray
        buttonTitles = buttonTitlesArray
        buttonsWithImages = false
    } else {
        print("Initilization failed, the VC ID array count does not match the button titles array count.")
    }
}

public func initializeWithVCIDsArrayAndButtonImagesArray (VCIDsArray: [String], buttonImagesArray: [UIImage]) {
    // Important - Images Array must Have The Same Number Of Items As The viewControllerIDs Array
    if VCIDsArray.count == buttonImagesArray.count {
        viewControllerIDs = VCIDsArray
        buttonImages = buttonImagesArray
        buttonsWithImages = true
    } else {
        print("Initilization failed, the VC ID array count does not match the button images array count.")
    }
}

public func loadPage(page: Int) {
    // If it's outside the range of what you have to display, then do nothing
    guard page >= 0 && page < viewControllerIDs.count else { return }

    // Do nothing if the view is already loaded.
    guard pageViews[page] == nil else { return }

    print("Loading Page \(page)")

    // The pageView instance is nil, create the page
    var frame = scrollView.bounds
    frame.origin.x = frame.size.width * CGFloat(page)
    frame.origin.y = 0.0

    // Look for the VC by its identifier in the storyboard and add it to the scrollview
    let newPageView = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: viewControllerIDs[page])
    newPageView.view.frame = frame
    scrollView.addSubview(newPageView.view)

    // Replace the nil in the pageViews array with the VC just created
    pageViews[page] = newPageView
}

public func loadVisiblePages() {
    // First, determine which page is currently visible
    let pageWidth = scrollView.frame.size.width
    let page = Int(floor((scrollView.contentOffset.x * 2.0 + pageWidth) / (pageWidth * 2.0)))

    // Work out which pages you want to load
    let firstPage = page - 1
    let lastPage = page + 1

    // Load pages in our range
    for index in firstPage...lastPage {
        loadPage(page: index)
    }
}

public func barButtonAction(sender: UIButton?) {
    let index = sender!.tag
    let pagesScrollViewSize = scrollView.frame.size

    scrollView.setContentOffset(CGPoint(x: pagesScrollViewSize.width * CGFloat(index), y: 0), animated: true)

    currentPage = index
}

// MARK: - Orientation Handling Functions -

public func alignSubviews() {
    let pageCount = viewControllerIDs.count

    // Setup the new frames
    scrollView.contentSize = CGSize(width: CGFloat(pageCount) * scrollView.bounds.size.width, height: scrollView.bounds.size.height)
    topBar.frame = CGRect(x: 0, y: 0, width: containerVieww.frame.size.width, height: topBarHeight)
    blurView?.frame = topBar.bounds
    animatedBar.frame.size = CGSize(width: (containerVieww.frame.size.width / (CGFloat)(viewControllerIDs.count)) * 0.8, height: animatedBarHeight)
    if barShadow {
        shadowView.frame.size = CGSize(width: containerVieww.frame.size.width, height: 4)
        shadowViewGradient.frame = shadowView.bounds
    }

    // Set the new frame of the scrollview contents
    for (index, controller) in pageViews.enumerated() {
        controller?.view.frame = CGRect(x: CGFloat(index) * scrollView.bounds.size.width, y: 0, width: scrollView.bounds.size.width, height: scrollView.bounds.size.height)
    }

    // Set the new frame for the top bar buttons
    var buttonsXPosition: CGFloat = 0
    for button in barButtons {
        button?.frame = CGRect(x: buttonsXPosition, y: 0, width: containerVieww.frame.size.width / CGFloat(viewControllerIDs.count), height: topBarHeight)
        buttonsXPosition += containerVieww.frame.size.width / CGFloat(viewControllerIDs.count)
    }
}

func applicationWillEnterBackground() {
    //Save the current page
    currentPage = Int(scrollView.contentOffset.x / scrollView.bounds.size.width)
    print("Haydar")
}

func orientationWillChange() {
    //Save the current page
    currentPage = Int(scrollView.contentOffset.x / scrollView.bounds.size.width)
}

func orientationDidChange() {
    //Update the view
    alignSubviews()
    scrollView.contentOffset = CGPoint(x: CGFloat(currentPage) * scrollView.frame.size.width, y: 0)
}

func applicationWillEnterForeground() {
    alignSubviews()
    scrollView.contentOffset = CGPoint(x: CGFloat(currentPage) * scrollView.frame.size.width, y: 0)
    initializeWithVCIDsArrayAndButtonTitlesArray(VCIDsArray: buttonTitles, buttonTitlesArray: buttonTitles)
    print("ForegroundHound")
}

public func scrollViewDidEndDecelerating(scrollView: UIScrollView) {
    let previousPage : NSInteger = currentPage
    let pageWidth : CGFloat = scrollView.frame.size.width
    let fractionalPage = scrollView.contentOffset.x / pageWidth
    let page : NSInteger = Int(round(fractionalPage))
    if (previousPage != page) {
        currentPage = page;
    }
}


deinit {
    NotificationCenter.default.removeObserver(self)
    print("deinittta")
}

}

extension SwiftPages: UIScrollViewDelegate {


public func scrollViewDidScroll(_ scrollView: UIScrollView) {
    // Load the pages that are now on screen
    loadVisiblePages()

    // The calculations for the animated bar's movements
    // The offset addition is based on the width of the animated bar (button width times 0.8)
    let offsetAddition = (containerVieww.frame.size.width / CGFloat(viewControllerIDs.count)) * 0.1
    animatedBar.frame = CGRect(x: (offsetAddition + (scrollView.contentOffset.x / CGFloat(viewControllerIDs.count))), y: animatedBar.frame.origin.y, width: animatedBar.frame.size.width, height: animatedBar.frame.size.height)
}

}

SwiftPages updateUI不适用于Swift 3

0 个答案: