ios - SwiftUI 中的选择器

Question

我正在尝试使用在 SwiftUI 中为 UIKit 创建的第 3 方库，例如 BetterSegmentedControl 库 ( https://github.com/gmarm/BetterSegmentedControl )需要 Selector 女巫采用 objc 函数来处理用户输入。

在 SwiftUI 中甚至有处理这个问题的方法吗？

struct ContentView : UIViewRepresentable {
    func makeUIView(context: Context) -> BetterSegmentedControl {
        BetterSegmentedControl()
    }


    func updateUIView(_ view: BetterSegmentedControl, context: Context) {
        let control = BetterSegmentedControl(
            frame: CGRect(x: 0, y: 0, width: 300, height: 44),
            segments: LabelSegment.segments(withTitles: ["One", "Two", "Three"],
                                            normalTextColor: .lightGray,
                                            selectedTextColor: .white),
            index: 1,
            options: [.backgroundColor(.darkGray),
                      .indicatorViewBackgroundColor(.blue)])

        view.addSubview(control)

        @objc func controlValueChanged(_ sender: BetterSegmentedControl) {

        }

        control.addTarget(self, action: #selector(controlValueChanged(_:)), for: .valueChanged)
        view.addSubview(control)

    }
}

这段代码有两个错误:

@objc can only be used with members of classes, @objc protocols, and concrete extensions of classes


Argument of '#selector' cannot refer to local function 'controlValueChanged'

Answer 1

我最终添加了一个辅助类:

struct MainView: View {

let helper = MainViewHelper()

// somewhere, sometimes...
vc.navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .cancel, target: self.helper, action: #selector(self.helper.closeAction))

}

class MainViewHelper {
  @objc func closeAction() {
    // whatever
  }
}