如何让viewForZoomingInScrollView在Xcode中跨多个UIViewControllers工作？

import UIKit

class CustomScrollView: UIScrollView, UIScrollViewDelegate {
    override init(frame: CGRect) {
        super.init(frame: frame)
        self.delegate = self
        self.maximumZoomScale = 3.0
        self.minimumZoomScale = 1.0
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        self.delegate = self
        self.maximumZoomScale = 3.0
        self.minimumZoomScale = 1.0
    }
    
    func viewForZooming(in scrollView: UIScrollView) -> UIView? {
        // 返回需要进行缩放的视图
        return self.subviews.first
    }
}

class ViewController1: UIViewController, UIScrollViewDelegate {
    var customScrollView: CustomScrollView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        customScrollView = CustomScrollView(frame: self.view.bounds)
        self.view.addSubview(customScrollView)
        
        // 添加需要进行缩放的视图到customScrollView中
        let zoomView = UIView(frame: CGRect(x: 0, y: 0, width: 200, height: 200))
        zoomView.backgroundColor = UIColor.red
        customScrollView.addSubview(zoomView)
        
        customScrollView.contentSize = zoomView.bounds.size
        customScrollView.delegate = self
    }
    
    // 实现其他UIScrollViewDelegate方法，根据需要进行自定义操作
}

class ViewController2: UIViewController, UIScrollViewDelegate {
    var customScrollView: CustomScrollView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        customScrollView = CustomScrollView(frame: self.view.bounds)
        self.view.addSubview(customScrollView)
        
        // 添加需要进行缩放的视图到customScrollView中
        let zoomView = UIView(frame: CGRect(x: 0, y: 0, width: 300, height: 300))
        zoomView.backgroundColor = UIColor.blue
        customScrollView.addSubview(zoomView)
        
        customScrollView.contentSize = zoomView.bounds.size
        customScrollView.delegate = self
    }
    
    // 实现其他UIScrollViewDelegate方法，根据需要进行自定义操作
}