Why the "Use of undeclared type UITableView" happened in Swift?

Question

I am new to Swift. I created a second swift file call DeviceInfo.swift and add a UIViewcontroller in Main.storyboard.

I also add a UITableView in UIViewcontroller(DeviceInfo).

But the error Use of undeclared type 'UITableView' show after I connect the UITableView to DeviceInfo.swift via command + left. The error show like the following.

Question

1. Why the Use of undeclared type 'UITableView' happened ? How to solve it ?

2. Show I connect the dataSource and delegate to UIViewcontroller(DeviceInfo)?

Thanks in advance.

Answer 1

1.import UIKit

2.To connect delegate and dataSource, click the point and drag to your tableView.

Answer 2

You need to add import UIKit at the top of your file, in the area where you've already got import Foundation. Without UIKit imported, your object doesn't know what a UITableView is.