视图中的所有UITextField [英] All UITextField in a View

问题描述

在viewDidLoad中，我将使用下面的代码扫描所有UITextField和set addTarget。我有3个UITextField但只找到其中​​的一个。

In viewDidLoad I would scan all UITextField and a set addTarget with the code below. I have 3 UITextField but only 1 of that is found.

   for subview in self.view.subviews
   {
        println(subview)
       if (subview.isKindOfClass(UITextField))
       {
            var textField = subview as UITextField
                textField.addTarget(self, action: "textFieldDidReturn:", forControlEvents: UIControlEvents.EditingDidEndOnExit)

                textField.addTarget(self, action: "textFieldDidBeginEditing:", forControlEvents: UIControlEvents.EditingDidBegin)
            }

    }

视图非常简单，专为锻炼而设计。 1个UIimageView，3个UITextField，1个按钮，1个标签。但println（子视图）只显示

The view is very simple, built for exercise. 1 UIimageView, 3 UITextField, 1 button, 1 label. But the println(subview) display only

<UITextField: 0x7a739cf0; frame = (57 430; 290 30); text = ''; clipsToBounds = YES; opaque = NO; autoresize = RM+BM; layer = <CALayer: 0x7a739c90>>
<UIImageView: 0x7a742d70; frame = (0 0; 0 0); autoresize = RM+BM; userInteractionEnabled = NO; layer = <CALayer: 0x7a742ef0>>
<_UILayoutGuide: 0x7a7430d0; frame = (0 0; 0 0); hidden = YES; layer = <CALayer: 0x7a743270>>
<_UILayoutGuide: 0x7a743650; frame = (0 0; 0 0); hidden = YES; layer = <CALayer: 0x7a7436d0>>

找到并设置第一个UITextField，其他不是。为什么？我哪里错了？

The first UITextField is found and set, the others not. Why? Where am I wrong?

换句话说。扫描视图中所有对象的正确方法是什么？

In other word. What is the right way to scan all the objects in a view?

谢谢

推荐答案

问题仅在于您过早运行代码。您的代码位于视图控制器超类的 viewDidLoad 中。那时，它的视图已加载，但其子类的视图没有 - 并且子类的视图是所有子视图的位置。因此，您获取日志记录代码的结果虽然令人惊讶，但完全正确 - 代码运行时。

The problem is merely that you are running your code too soon. Your code is in your view controller superclass's viewDidLoad. At that time, its view has loaded, but its subclass's view has not - and the subclass's view is where all the subviews are. So the result you are getting for your logging code, while surprising, is perfectly correct — at the moment that the code runs.

只需移动将您的日志代码转换为 viewDidAppear：的实现，或者在接口完全就绪后调用的其他方法，您将获得结果你期待。我用你的项目测试了它，它工作正常。

Just move your logging code into an implementation of viewDidAppear: or some other method that is called after the interface is completely ready, and you'll get the result you expect. I tested that with your project and it works fine.

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