关于“声明仅在文件范围内有效"

About quot;Declaration is only valid at file scopequot;(关于“声明仅在文件范围内有效)

问题描述

我有一个类和扩展 Swift 文件.将我在另一个文件中声明的委托添加到类后，Xcode 显示此错误

I have a class and extension Swift file. After adding a delegate that I declared in another file to the class, Xcode shows this error

声明仅在文件范围内有效

Declaration is only valid at file scope

在延长线上.不知道是什么问题.

at the extension line. I don't know what the problem is.

谁能帮我解决它?

class ListViewController: UIViewController, AddItemViewControllerDelegate {...}

extension ListViewController: UITableViewDataSource{
    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        tableView.deselectRowAtIndexPath(indexPath, animated: true)
        performSegueWithIdentifier("ShowDetail", sender: indexPath)
    }

}

推荐答案

错误出现在您的 ... 中——该错误意味着您的 ListViewController 类没有t 被关闭，因此扩展被解释为嵌套在内部，如下所示:

The error is somewhere in your ... — that error means that your ListViewController class didn't get closed, so the extension is being interpreted as nested inside, like this:

class ListViewController {
    ...
    extension ListViewController {
    }
}

找到丢失的右大括号，你应该解决问题.

Find the missing closing brace and you should solve the problem.

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