如何在iOS中获取主叫方呼叫的视频窗口？

import AVFoundation
import UIKit

class ViewController: UIViewController {
    var captureSession: AVCaptureSession?
    var videoPreviewLayer: AVCaptureVideoPreviewLayer?
    var videoWindowView: UIView?
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建并配置捕捉会话
        captureSession = AVCaptureSession()
        captureSession?.sessionPreset = .high
        
        // 获取摄像头设备
        guard let videoDevice = AVCaptureDevice.default(for: .video) else { return }
        
        // 创建摄像头输入
        guard let videoInput = try? AVCaptureDeviceInput(device: videoDevice) else { return }
        
        // 将摄像头输入添加到捕捉会话
        if (captureSession?.canAddInput(videoInput) ?? false) {
            captureSession?.addInput(videoInput)
        }
        
        // 创建视频预览层
        videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession!)
        videoPreviewLayer?.videoGravity = AVLayerVideoGravity.resizeAspectFill
        videoPreviewLayer?.frame = view.bounds
        
        // 将视频预览层添加到视图层级
        view.layer.addSublayer(videoPreviewLayer!)
        
        // 创建视频窗口视图
        videoWindowView = UIView(frame: CGRect(x: 100, y: 100, width: 200, height: 150))
        videoWindowView?.backgroundColor = UIColor.red
        
        // 将视频窗口视图添加到视图层级
        view.addSubview(videoWindowView!)
        
        // 开始捕捉会话
        captureSession?.startRunning()
    }
}