swift - ScrollView 不显示组件

Question

我已经开始以编程方式创建 UI，但遇到了困难。我在 View 中添加了模糊效果，然后在只有一个按钮但不显示的模糊滚动中添加了模糊效果。通过调试我可以看到里面有一个按钮。可能出了什么问题？

(lldb) po blurEffectViewFilters.contentView.subviews
▿ 1 element
  - 0 : <UIScrollView: 0x7fd5958a5e00; frame = (0 0; 0 0); clipsToBounds = YES; gestureRecognizers = <NSArray: 0x600000253020>; layer = <CALayer: 0x6000002369c0>; contentOffset: {0, 0}; contentSize: {320, 568}>


(lldb) po blurEffectViewFilters.contentView.subviews[0].subviews
▿ 1 element
  - 0 : <UIButton: 0x7fd593f3bde0; frame = (0 0; 100 50); opaque = NO; layer = <CALayer: 0x600000236a40>>


   func initFiltersView() {
        blurEffectFilters = UIBlurEffect(style: UIBlurEffectStyle.dark)
        blurEffectViewFilters = UIVisualEffectView(effect: blurEffectFilters)
        blurEffectViewFilters.frame = view.bounds
        blurEffectViewFilters.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        blurEffectViewFilters.isHidden = true

        scrollView = UIScrollView()
        scrollView.delegate = self
        scrollView.contentSize = blurEffectViewFilters.bounds.size

        doneButton = UIButton(frame: CGRect(x: 0, y: 0, width: 100, height: 50))
        doneButton.backgroundColor = .white
        doneButton.setTitle("Done", for: .normal)

        scrollView.addSubview(doneButton)

        blurEffectViewFilters.contentView.addSubview(scrollView)

        view.addSubview(blurEffectViewFilters)
    }

提前致谢!

Answer 1

看起来您从未设置 ScrollView 的框架:

- 0 : <UIScrollView: 0x7fd5958a5e00; frame = (0 0; 0 0); clipsToBounds ...

在 initFiltersView() 代码中，您设置的是 contentSize，而不是框架。