使用没有故事板的BWWalkthrough库，演练定制

Question

我正在使用BWWalkthrough库作为我的个人漫游。实现起来非常简单，但是我在BWWalkthroughViewController上有一个错误:我不会使用故事板来创建这个主控制器，所以我已经通过代码创建了我的自定义视图，然后在viewDidLoad of BWWalkthroughViewController ive中设置了视图和pageControl。其余代码与github存储库中的示例相同。

这就是viewDidLoad of BWWalkthroughViewController：

override func viewDidLoad() {
    super.viewDidLoad()
    let welcomeview: WelcomeView = WelcomeView() // my custom view
    view = welcomeview
    self.pageControl = welcomeview.pageControl 
    ...
}

而且，因为它是第一个视图，所以rootViewController是用修改了viewDidLoad的BWWalkthroughViewController设置的。因此，我有一个在AppDelegate.swift中设置本演练的功能：

func showWelcomeView() -> BWWalkthroughViewController{
    let storyboard = UIStoryboard(name: "Welcome", bundle: nil)

    let walkthrough: BWWalkthroughViewController = BWWalkthroughViewController()
    let page_zero = storyboard.instantiateViewControllerWithIdentifier("walk_0") as! UIViewController
    let page_one = storyboard.instantiateViewControllerWithIdentifier("walk_1") as! UIViewController
    let page_two = storyboard.instantiateViewControllerWithIdentifier("walk_2") as! UIViewController
    let page_three = storyboard.instantiateViewControllerWithIdentifier("walk_3") as! UIViewController
    let page_four = storyboard.instantiateViewControllerWithIdentifier("walk_4") as! UIViewController

    walkthrough.delegate = self
    walkthrough.addViewController(page_zero)
    walkthrough.addViewController(page_one)
    walkthrough.addViewController(page_two)
    walkthrough.addViewController(page_three)
    walkthrough.addViewController(page_four)




    return walkthrough
}

我在这里使用这个功能：

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    // Override point for customization after application launch.


    self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
    self.window?.rootViewController = showWelcomeView() // func usedhere
    return true
}

该应用程序运行时没有错误。我可以看到我的自定义视图和所有4个子视图(walk_0.walk_4)，但我不能正确地滑动它们:滚动是免费的，不会在每一页上停止。

所以..。我的自定义视图错过了一些步骤？请救救我！

这是一个来自我的IPhone的屏幕截图，滚动图位于两个子视图之间：

​

Answer 1

我在BWWalkthroughViewController中使用滚动视图的属性修复了这个问题。

override func viewDidLoad() {
    super.viewDidLoad()

   ..

    scrollview.pagingEnabled = true
}

干得不错，但不知道为什么。该滚动视图的默认设置为init中设置的pagingeEnabled = true：

required init(coder aDecoder: NSCoder) {
    // Setup the scrollview
    scrollview = UIScrollView()
    scrollview.showsHorizontalScrollIndicator = false
    scrollview.showsVerticalScrollIndicator = false
    scrollview.pagingEnabled = true  // Default of scrollview

    // Controllers as empty array
    controllers = Array()

    super.init(coder: aDecoder)
}

Answer 2

在BWWalkthroughViewController类中添加以下函数。

override func viewDidLayoutSubviews(){
    // Constraints
        let metricDict = ["w":view.bounds.size.width,"h":view.bounds.size.height]

        // - Generic cnst
        for vc in controllers {
            vc.view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("V:[view(h)]", options:[], metrics: metricDict, views: ["view":vc.view]))
            vc.view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("H:[view(w)]", options:[], metrics: metricDict, views: ["view":vc.view]))
            scrollview.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("V:|-0-[view]|", options:[], metrics: nil, views: ["view":vc.view,]))
        }
    }

从addViewController函数中删除以下行

// Constraints
let metricDict = ["w":vc.view.bounds.size.width,"h":vc.view.bounds.size.height]
    // - Generic cnst
        vc.view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("V:[view(h)]", options:[], metrics: metricDict, views: ["view":vc.view]))
        vc.view.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("H:[view(w)]", options:[], metrics: metricDict, views: ["view":vc.view]))
        scrollview.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("V:|-0-[view]|", options:[], metrics: nil, views: ["view":vc.view,]))

Answer 3

你有没有连接

@IBOutlet var pageControl:UIPageControl?

在BWWalkthroughViewController中，页面控制器在视图控制器中？

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