xcode 使用未声明的类型 UIViewController
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use of undeclared type UIViewController
提问by dgelinas21
I have not changed anything major in this swift file, yet for some reason when I went to run my app I got a new error stating "Use of undeclared type UIViewController" in the first line of my swift file. I have tried cleaning and checking the targets, but am unable to figure out the issue.
我没有更改此 swift 文件中的任何主要内容，但出于某种原因，当我去运行我的应用程序时，我在 swift 文件的第一行收到一个新错误，指出“使用未声明的类型 UIViewController”。我曾尝试清理和检查目标，但无法找出问题所在。
I am getting an errors on every line below, excluding the import statements
我在下面的每一行都收到错误消息，不包括导入语句
import Foundation
import FirebaseAuth
import FirebaseDatabase
public class User: UIViewController {
@IBOutlet weak var _Fname: UITextField!
@IBOutlet weak var _Lname: UITextField!
@IBOutlet weak var _Email: UITextField!
@IBOutlet weak var _Password1: UITextField!
@IBOutlet weak var _Password2: UITextField!
Please let me know if you have any thoughts on why this may be occurring. Thanks in advance!
如果您对为什么会发生这种情况有任何想法，请告诉我。提前致谢！
回答by unniverzal
You probably forgot to import UIKiton top of your file. Without UIKitimported, your object doesn't know what a UIViewControlleris.
你可能忘记了import UIKit在你的文件之上。如果没有UIKit导入，您的对象不知道 aUIViewController是什么。
