如何知道 UIKit 视图控制器中的 swiftUI 事件? ||如何提供 swiftUI 和 uikit 之间的通信

How to know swiftUI event in UIKit view controller? || How to provide communication between swiftUI and uikit

我是 swiftUI 的新手。我想在我当前的 UIkit 项目中添加 swiftUI 视图,我为此创建了一个演示,现在我卡在了其中。

这是我的 ViewController 代码:


import UIKit
import SwiftUI

class ViewController: UIViewController {
    
    
    @IBOutlet weak var stepperContenerView: UIView!
    @IBOutlet weak var btn:UIButton!
    
    
    lazy var stepView = StepperView(intialCount: 1)
    lazy var swiftUIHostingView = UIHostingController(rootView: stepView)
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        stepperContenerView.addSubview(swiftUIHostingView.view)
        addChild(swiftUIHostingView)
//        stepView.delegate = self

        swiftUIHostingView.view.frame = stepperContenerView.bounds
        stepperContenerView.addConstrained(subview: swiftUIHostingView.view)
        swiftUIHostingView.didMove(toParent: self)
    }
    @IBAction func onClickBtn(_ sender: UIButton) {
        let alert = UIAlertController(title: "Stepper count", message: "Current value : \(stepView.getCount())", preferredStyle: UIAlertController.Style.alert)
        alert.addAction(UIAlertAction(title: "ok", style: UIAlertAction.Style.default, handler: nil))
        self.present(alert, animated: true, completion: nil)
    } 
}
 
//extension ViewController:OnClickStepperButton {
//    func updateCount(count: Int) {
//        print("Test")
//        lbl.text = "Stepper count is - \(count)"
//    }
//}


这是我的 swiftUI 步进器视图代码:-


import SwiftUI

protocol OnClickStepperButton {
    func updateCount(count:Int)
}

struct StepperView: View {
    @State private var count:Int = 1
    var delegate:OnClickStepperButton?
    
    init(intialCount:Int){
        self.count = intialCount
    }
    
    var body: some View {
        HStack(alignment: .center, spacing: 10) {
            Button("+", action: {
                count += 1
                print(count)
//                delegate?.updateCount(count: count)
            })
            
            Text("\(count)")
                .frame(minWidth: 40,minHeight: 40)
                .background(Color.white)
                .foregroundColor(.black)
                .scaledToFill()
                
            Button("-", action: {
                if count > 1 {
                    count -= 1
                    print(count)
                }
//                delegate?.updateCount(count: count)
            })
            
        }
        .font(.system(size: 22, weight: .medium, design: .serif))
        .frame(minWidth: 120, minHeight: 40, alignment: .center)
        .background(Color.blue)
        .foregroundColor(Color.white)
        .cornerRadius(20)
    
    }
    public func getCount() -> Int {
        count
    }

}

struct Stepper_Previews: PreviewProvider {
    static var previews: some View {
        StepperView(intialCount: 1)
            .previewLayout(.fixed(width: 300, height: 70))
    }
}

既没有委托调用,也没有在单击按钮时获取更新值。 (代表们有意发表评论以强调其不起作用,请取消评论以进行检查)。

delegate 变量永远不会按原样设置。

您需要删除 ?从 SwiftUI 视图中的变量,因此您被迫在初始化时提供一个值。

此外,删除自定义初始化程序。