我的问题不在上面。太差劲了。但我想我应该把它列在这里，也许它能帮助到别人。

I have a tableViewController that is my "base" controller and then I create subclasses of this controller. I was writing all my code in the tableView:didSelectRowAtIndexPath routine in the "base" class. Completely forgetting that by default this routine had also been created (albeit with no code that did anything) in all of my subclasses as well. So when I ran my app, it ran the subclass version of the code, did nothing, and made me sad. So of course, once I removed the routine from the subclasses, it used mt "base" class routine and I'm in business.

我知道。别笑。但也许这能帮别人省下我浪费的一小时…

我不确定是否有人滚动到足够远的地方看到这个答案，但由于这是关于这个主题最受欢迎的问题，而答案并不在那里，我将添加它:

从Xcode 9 / Swift 4开始，所有Objective-C方法都应该标记为@objc。编译器做了一个合理的工作，识别它应该应用在哪里，但它不计算继承。例如:

class Delegate: NSObject, UITableViewDelegate {
}

class SuperDelegate: Delegate {
    override func tableView(_ tableView: UITableView, willSelectRowAt indexPath: IndexPath) -> IndexPath? { return indexPath }
}

这将不会产生任何警告、崩溃或构建错误。但是你的行不会被调用，直到你添加@objc:

@objc class SuperDelegate: Delegate {
    override func tableView(_ tableView: UITableView, willSelectRowAt indexPath: IndexPath) -> IndexPath? { return indexPath }
}

记住在viewDidLoad方法中设置数据源和委托，如下所示:

[self.tableView setDelegate:self];

[self.tableView setDataSource:self];

即使另一个答案已经被接受，我将为观察这个问题的人补充一个可能的问题和解决方案:

If you have automatic reference counting (ARC) turned on, you may find that even after assigning your controller as a delegate of the view, the view's messages to the controller are not being received because ARC is deleting the controller. Apparently the UITableView's delegate pointer does not count as a reference for the ARC, so if that is the only reference to it, the controller will be dealloc'd. You can verify whether or not this is happening by implementing the dealloc method on the controller and setting a breakpoint or NSLog call there.

解决方案是在其他地方使用强引用跟踪控制器，直到确定不再需要它为止。

如果您的表视图处于编辑模式(例如。[tableView setEditing:YES animated:NO];)，你需要设置tableView。allowsSelectionDuringEditing = YES;

我刚刚有了这个，就像过去发生在我身上的一样，它没有工作，因为我在尝试添加方法时没有注意自动完成，我实际上最终实现了tableView:didDeselectRowAtIndexPath:而不是tableView:didSelectRowAtIndexPath:。