当我从自定义 UIViewController 导航到 TabBarController 的第二个选项卡时,我遇到了问题,这当然是另一个 UIViewController。
如果我从 AdminPanel 导航到 Products 不会崩溃,因为我有一个从 Products 到 AdminPanel 的 push
。但是从 AdminPanel 到 Cart 我没有任何 push
。
这是一张带有错误的图片:
这是错误:“无法将‘MyAppName.AdminPanelViewController’ (0x10e878418) 类型的值转换为‘MyAppName.ProductsViewController’ (0x10e877e00)。”
这是我的设计:
这是我的代码:
// PRODUCTS VC
class ProductsViewController: UIViewController{
var selectedProductsArray = [Product]()
var priceForSelectedProductsArray = [Float]()
// Func which is using GestureRecognition to access the Admin Panel when we press on User Avatar
func accessToAdminPanel(){
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(ProductsViewController.adminImageTapped(gesture:)))
userAvatarImageView.addGestureRecognizer(tapGesture)
}
// Function to open the AdminPanelViewController
@objc func adminImageTapped(gesture: UIGestureRecognizer) {
let storyBoard : UIStoryboard = UIStoryboard(name: Constants.nameOfMainSB, bundle:nil)
let adminPanelVC = storyBoard.instantiateViewController(withIdentifier: Constants.adminPanelStoryboard) as! AdminPanelViewController
self.navigationController?.pushViewController(adminPanelVC, animated: true)
}
// Func which will add the product into an array of products when the user press Add To Cart
func didTapAddToCart(_ cell: ProductTableViewCell) {
let indexPath = self.productsTableView.indexPath(for: cell)
addProduct(at: indexPath!)
selectedProductsArray.append(productsArray[(indexPath?.row)!]) // Append products for cart
priceForSelectedProductsArray.append(productsArray[(indexPath?.row)!].price) // Append prices for selected products
}
}
// CART VC
class CartViewController: UIViewController {
var productsInCartArray = [Product]()
var productPricesArray = [Float]()
// Append the selectedProducts into productsInCartArray using the TabBarController
func fetchSelectedProducts() {
// ------------------HERE IS CRASHING AT THIS LINE -----------------------
productsInCartArray = ((self.tabBarController?.viewControllers![0] as! UINavigationController).topViewController as! ProductsViewController).selectedProductsArray
productPricesArray = ((self.tabBarController?.viewControllers![0] as! UINavigationController).topViewController as! ProductsViewController).priceForSelectedProductsArray
totalSum = productPricesArray.reduce(0, +)
}
}
如果您无法弄清楚这部分代码是哪里崩溃了,我可以给您 git 源代码的链接,因为我没有什么可隐藏的。
如果您正在阅读本文,非常感谢您抽出宝贵时间,我希望您能帮助我,因为我花了半天时间尝试找到解决方案来修复导致我的应用程序崩溃的错误。
最佳答案
topViewController 现在是 admin 而不是 products 所以你需要在索引 0 处获取 VC,它是 products
productsInCartArray = ((self.tabBarController?.viewControllers![0] as! UINavigationController).viewControllers[0] as! ProductsViewController).selectedProductsArray
关于ios - 从自定义 UIViewController 导航到 TabBarController 没有 segue,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/51140937/