滚动的UITableView向上滑动至屏幕的顶部斯威夫特

Question

我想创建一个非常简单的布局，类似条纹的iOS应用程序有哪些，你可以在这里看到：https://stripe.com/img/dashboard_iphone/screencast.mp4

在围绕0：06S表视图刷卡它会移动到窗口的顶部。

是否有任何雨燕简单的指令，显示这种设计模式我看到它无处不在，但不知道如何创建它

Answer 1

1. 添加一个UIView
2. 子类的UIView与自定义类

在您自定义的UIView，你需要几个变量和几个覆盖。确保用户交互在你的故事板的UIView的启用，然后在您的自定义类加载：

var startPosition: CGPoint? 
var originalHeight: CGFloat? 

之后，添加以下内容：

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) { 
    let touch = touches.first 
    startPosition = touch?.locationInView(self) 
    originalHeight = self.frame.height 
} 

override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) { 
    let touch = touches.first 
    let endPosition = touch?.locationInView(self) 
    let difference = endPosition!.y - startPosition!.y 
    let newFrame = CGRectMake(self.frame.origin.x, self.frame.origin.y + difference, self.frame.width, self.frame.height - difference) 
    self.frame = newFrame 
} 

override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) { 

} 

Answer 2

在UIScrollView.h：

// When the user taps the status bar, the scroll view beneath the touch which is closest to the status bar will be scrolled to top, but only if its `scrollsToTop` property is YES, its delegate does not return NO from `shouldScrollViewScrollToTop`, and it is not already at the top. 
// On iPhone, we execute this gesture only if there's one on-screen scroll view with `scrollsToTop` == YES. If more than one is found, none will be scrolled. 
var scrollsToTop: Bool // default is YES. 

初始化滚动视图的委托（除非你已经有了，可能在你的viewDidLoad中），然后将其设置为true。

像这样：

myScrollView.scrollsToTop = true 

如果你想确保你的滚动视图委托允许这一点，从UIScrollViewDelegate的协议检查这个方法：

optional func scrollViewShouldScrollToTop(scrollView: UIScrollView) -> Bool // return a yes if you want to scroll to the top. if not defined, assumes YES 

请评论的任何问题。