如何使用变量中的某些数据推送到tabbar中查看？

Question

我有一个tabbar，其中包括：TabBar - HomeView - > UserProfileView - > Gallery - LeaderBoardView - SettingView - ........在这里，用户可以通过userProfileView选择各种选项（相机，图库，头像）在主视图中更改用户配置文件。 让我们说，用户选择图库，他/她去图库，选择图像，代码将推回到主视图，图像。 用户配置文件图像将更改，但标签栏控制器消失。 选择头像也是一样的情况。

由于我们需要将图像放在homeview中，因此无法推送到tabbar视图，因为图像的变量位于homeview中。 我们可以在homeview中推送到tabbar视图和图像数据吗？ 或者我们可以推送到homeview并显示标签栏控制器。

我是xcode / Swift的新手。 我正在尝试将测验应用作为练习。 我用过

NavigationController.pushviewController

以下是一些引用问题的代码。

    fileprivate func presentPhotoPickerController() {
        let myPickerController = UIImagePickerController()
        myPickerController.allowsEditing = true
        myPickerController.delegate = self
        myPickerController.sourceType = .photoLibrary
        self.present(myPickerController, animated: true)
    }

@IBAction func goToGalleryBtn(_ sender: Any) {
        if UIImagePickerController.isSourceTypeAvailable(.photoLibrary){
            PHPhotoLibrary.requestAuthorization { (status) in
                switch status {
                case .authorized:
                    self.presentPhotoPickerController()
                    break
                case .notDetermined:
                    if status == PHAuthorizationStatus.authorized{
                        self.presentPhotoPickerController()
                    }
                case .restricted:
                    let alert = UIAlertController(title: "Photo Library Restricted", message: "Photo Library access is restricted and cannot be accessed.", preferredStyle: .alert)
                    let okAction = UIAlertAction(title: "OK", style: .default)
                    alert.addAction(okAction)
                    self.present(alert, animated: true)
                case .denied:
                    let alert = UIAlertController(title: "Photo Library Denied", message: "Photo Library access was previously denied. Please update your Settings if you wish to change this.", preferredStyle: .alert)
                    let goToSettingsAction = UIAlertAction(title: "Go to Settings", style: .default){(action) in
                        DispatchQueue.main.async {
                            let url = URL(string: UIApplication.openSettingsURLString)!
                            UIApplication.shared.open(url, options: [:])
                        }
                    }
                    let cancelAction = UIAlertAction(title: "Cancel", style: .cancel)
                    alert.addAction(goToSettingsAction)
                    alert.addAction(cancelAction)
                    self.present(alert, animated: true)
                }
            }
        }
    }

    @IBAction func cancelBtn(_ sender: Any) {
        dismiss(animated: true, completion: nil)
    }
}

extension UserAvatarViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate{
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        if let image = info[.editedImage] as? UIImage{
            imageGallery = image
        }else if let image = info[.originalImage] as? UIImage{
            imageGallery = image
        }
        dismiss(animated: true, completion: nil)

        let storyBoard: UIStoryboard = UIStoryboard(name: "HomeViewController", bundle: nil)
        let homeVC = storyBoard.instantiateViewController(withIdentifier: "HomeVC") as! HomeViewController
        homeVC.imageView = imageGallery
//        self.navigationController?.pushViewController(homeVC, animated: true)
        self.navigationController?.popViewController(animated: true)
    }

    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
        dismiss(animated: true, completion: nil)
    }
}

顺便说一句，我对每个视图控制器都使用了不同的故事板。

Answer 1

我想，你的问题是使用didFinishPickingMediaWithInfo方法。 您正在创建HomeViewController的新对象，而不是从tabbar中选择控制器。我假设您已将tabbarcontroller设置为窗口上的rootviewcontroller 。

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
    if let image = info[.editedImage] as? UIImage{
        imageGallery = image
    }else if let image = info[.originalImage] as? UIImage{
        imageGallery = image
    }
    dismiss(animated: true, completion: nil)

    let appDel = UIApplication.shared.delegate as! AppDelegate
    let tabbar = appDel.window.rootViewController as TabbarViewController
    // if you know the index of the controller on tabbar, you can directly access it 
    let homeVC = tabbar.viewControllers[0] as! HomeViewController
    homeVC.imageView = imageGallery
    self.navigationController?.popViewController(animated: true)
}

如果不是窗口的rootViewController请告诉我你是如何设置tabbar的

Answer 2

像这样更新你的imagePickerController(picker: didFinishPickingMediaWithInfo)方法

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
    if let image = info[.editedImage] as? UIImage{
        imageGallery = image
    }else if let image = info[.originalImage] as? UIImage{
        imageGallery = image
    }
    dismiss(animated: true, completion: nil)

    //Assuming your viewcontroller hierarchy is
    // TabbarVC -> HomeVC -> GalleryVC -> ImagePickerVC
    if let homeVC = self.parent as? HomeViewController {
        homeVC.imageView = imageGallery
    }

    self.navigationController?.popViewController(animated: true)
}

并在HomeViewController viewWillAppear中更新图像。 希望它能满足您的需求。

Answer 3

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
    if let image = info[.editedImage] as? UIImage{
        imageGallery = image
    }else if let image = info[.originalImage] as? UIImage{
        imageGallery = image
    }
    dismiss(animated: true, completion: nil)

    let storyBoard:UIStoryboard = UIStoryboard(name: "TabBarViewController", bundle: nil)
    let tabBarVC = storyBoard.instantiateViewController(withIdentifier: "TabBarVC") as! UITabBarController
    let appDelegate = UIApplication.shared.delegate as! AppDelegate
    appDelegate.window?.rootViewController = tabBarVC
    let navBar = tabBarVC.viewControllers![0] as! UINavigationController
    let homeVC = navBar.topViewController as! HomeViewController
    homeVC.imageView = imageGallery
    self.navigationController?.popViewController(animated: true)
}

这终于奏效了。 感谢Hisenberg和Najeeb ur Rehman向我提供了使用Tab bar视图控制器及其子项的提示。