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我添加了两个视图控制器到我的滚动视图,并在两个视图控制器上都有动画,但这些动画只能在vc显示时调用。相反,当第一个vc显示时,两个动画都正在执行。如何将视图控制器添加到滚动视图,但只有在滚动视图显示vc时才实例化视图控制器?
func setUpScrollView() {
for i in 0..<2 {
let vc = NewViewController()
self.addChildViewController(vc)
scrollView.addSubview(vc.view)
vc.didMove(toParentViewController: self)
var frame: CGRect = vc.view.frame
frame.origin.x = self.view.frame.width * CGFloat(i)
vc.view.frame = frame
self.scrollView.contentSize = CGSize(width: self.view.frame.width * CGFloat(2), height: self.view.frame.size.height)
}
}
NewViewController
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
print("calling animation") //this is called twice immediatley after for loop, but only shows one vc.
}