第九天:SwiftEmbedSegueWithPageViewController

 

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　 

import UIKit

class ViewController: UIViewController, UIPageViewControllerDelegate, UIPageViewControllerDataSource {

    @IBOutlet weak var redBtn: UIButton!
    @IBOutlet weak var yellowBtn: UIButton!
    @IBOutlet weak var blueBtn: UIButton!
    
    var vcArr = NSMutableArray.init()
    var pageVC: UIPageViewController!
    var currentIndex: Int {
        get {
            if redBtn.isSelected {
                return redBtn.tag
            } else if yellowBtn.isSelected {
                return yellowBtn.tag
            } else if blueBtn.isSelected {
                return blueBtn.tag
            } else {
                return 0
            }
        }
        
        set {
            if newValue == 0 {
                redBtn.isSelected = true
                yellowBtn.isSelected = false
                blueBtn.isSelected = false
            } else if newValue == 1 {
                redBtn.isSelected = false
                yellowBtn.isSelected = true
                blueBtn.isSelected = false
            } else if newValue == 2 {
                redBtn.isSelected = false
                yellowBtn.isSelected = false
                blueBtn.isSelected = true
            }
        }
    }
    
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        
        let sb = UIStoryboard.init(name: "Main", bundle: nil)
        
        for tempID in ["RedViewController", "YellowViewController", "BlueViewController"] {
            let tempVC = sb.instantiateViewController(withIdentifier: tempID)
            vcArr.add(tempVC)
        }
        
        pageVC = self.childViewControllers.first as! UIPageViewController!
        pageVC.delegate = self
        pageVC.dataSource = self
        pageVC.setViewControllers([vcArr.object(at: 0) as! UIViewController], direction: .forward, animated: true, completion: nil)
        currentIndex = 0
    }

    @IBAction func handleBtnPressed(_ sender: UIButton) {
        if currentIndex != sender.tag {
            currentIndex = sender.tag
            pageVC.setViewControllers([vcArr.object(at: currentIndex) as! UIViewController], direction: .forward, animated: false, completion: nil)
        }
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? {
        let index = vcArr.index(of: viewController)
        if index - 1 < 0 {
            return nil
        } else {
            return vcArr.object(at: index - 1) as? UIViewController
        }
    }
    
    func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController? {
        let index = vcArr.index(of: viewController)
        if index + 1 >= vcArr.count {
            return nil
        } else {
            return vcArr.object(at: index + 1) as? UIViewController
        }
    }
    
    func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
        currentIndex = vcArr.index(of: pageViewController.viewControllers?[0] as Any)
    }
}