swift - 从 UIImagePickerController 中选择的图像未显示在 UIImageView 中

Question

我试图在持有 UIImageView 的 collectionViewCell 内显示 UIImagePickerController 中选定的图像。我可以打开并加载 imagePicker，但是当我选择图像时，UIImageView 仍然具有原始的占位符图像。我相信这与将 selectedImage 传递到实际单元格有关，而不是传递到登录 Controller 有关，但我不确定。预先感谢您的帮助!

//loginCell类LoginCell 类:UICollectionViewCell、UIImagePickerControllerDelegate、UINavigationControllerDelegate {

lazy var profileImageView: UIImageView = {
    let imageView = UIImageView()
    imageView.image = UIImage(named: "imagefile")
    //...
    imageView.addGestureRecognizer(UITapGestureRecognizer(target:self, action: #selector(handleSelectProfileImage)))
    imageView.isUserInteractionEnabled = true
    return imageView
}()

var loginController: LoginController?

func handleSelectProfileImage() {
    guard let loginController = delegate as? LoginController else {
        return
    }
    loginController.showImagePicker()
}

}

//登录 Controller 类类 LoginController:UIViewController、UICollectionViewDelegate、UICollectionViewDataSource、UICollectionViewDelegateFlowLayout、LoginControllerDelegate、UIImagePickerControllerDelegate、UINavigationControllerDelegate {

weak var loginCollectionView: UICollectionView!

func showImagePicker() {
    let picker = UIImagePickerController()
    picker.delegate = self
    picker.allowsEditing = true
    present(picker, animated: true, completion: nil)
}

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

    var selectedImageFromImagePicker: UIImage?

    if let editedImage = info["UIImagePickerControllerEditedImage"] as? UIImage {
        selectedImageFromImagePicker = editedImage
    } else if let originalImage = info["UIImagePickerControllerOriginalImage"] as? UIImage {
        selectedImageFromImagePicker = originalImage
    }

    if let selectedImage = selectedImageFromImagePicker {
        loginCell.profileImageView.image = selectedImage
    }
    dismiss(animated: true, completion: nil)
}

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

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let loginCell = collectionView.dequeueReusableCell(withReuseIdentifier: loginCellId, for: indexPath) as! LoginCell
        loginCell.delegate = self
        return loginCell
}

Answer 1

您将在此处创建 LoginCell 的新实例:

if let selectedImage = selectedImageFromImagePicker {
    let loginCell = LoginCell()
    loginCell.profileImageView.image = selectedImage
}

您应该删除第二行，以便您使用名为 loginCell 的类变量，而不是本地变量，根据您的代码，本地变量不会显示在任何地方。

if let selectedImage = selectedImageFromImagePicker {
    loginCell.profileImageView.image = selectedImage
}