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我的应用程序有一个 TabView (PageTabViewStyle)，每个选项卡内都有一个 UIViewRepresentable。我已经简化了代码以生成下面的最小可重现示例。问题是 makeUIView 在出现时被多次调用，在浏览页面时又被多次调用。

仅供参考，这在 iOS 14.0 中不是问题，但在 iOS 14.2 中正在发生。我目前正在使用 Xcode 12.2 Release Candidate。

import SwiftUI

struct MakeUIViewTest: View {
    var body: some View {
        TabView {
            CustomViewRepresentable(color: .red, index: 0)
            CustomViewRepresentable(color: .blue, index: 1)
            CustomViewRepresentable(color: .gray, index: 2)
        }
        .tabViewStyle(PageTabViewStyle())
    }
}

struct MakeUIViewTest_Previews: PreviewProvider {
    static var previews: some View {
        MakeUIViewTest()
    }
}

struct CustomViewRepresentable: UIViewRepresentable {
    
    var color: UIColor
    var index: Int
            
    func updateUIView(_ uiView: UIViewType, context: Context) {
        
    }
    
    func makeUIView(context: Context) -> UIView {
        print("MAKING UI VIEW NOW. INDEX \(index)")
        let view = UIView(frame: .zero)
        view.backgroundColor = color
        return view
    }

}

当屏幕出现时，控制台打印：

MAKING UI VIEW NOW. INDEX 0
MAKING UI VIEW NOW. INDEX 0
MAKING UI VIEW NOW. INDEX 0
MAKING UI VIEW NOW. INDEX 0
MAKING UI VIEW NOW. INDEX 0

当我向右滑动一次时，它会打印：

MAKING UI VIEW NOW. INDEX 1
MAKING UI VIEW NOW. INDEX 2
MAKING UI VIEW NOW. INDEX 1
MAKING UI VIEW NOW. INDEX 1
MAKING UI VIEW NOW. INDEX 1
MAKING UI VIEW NOW. INDEX 1
MAKING UI VIEW NOW. INDEX 2
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