在Swift项目中，

CartViewModel.swift

@objc public class CartViewModel: NSObject {

    let apiService: APIService

    var alertMessage: String? {
        didSet {
            self.showAlertClosure?()
        }
    }
    var isShow: Bool = false {
        didSet {
            self.updateStatus?()
        }
    }
    @objc public var dataCount: Int {
        return models.count
    }
}

ListViewController.h

NS_ASSUME_NONNULL_BEGIN

@class CartViewModel;

@interface ListViewController : UIViewController
@property (nonatomic,strong) CartViewModel *viewModel;

@end

NS_ASSUME_NONNULL_END

ListViewController.m

NSLog(@"%@",self.viewModel.dataCount); 

//访问任何属性都会出现此错误

  

在正向类对象'CartViewModel'中找不到属性'dataCount'