通过Objective-C中的类传递变量 [英] Passing variables through classes in Objective-C

问题描述

在我的场景中，我有2个视图控制器，一个连接到主视图，一个连接到第一个视图。

In my scenario I have 2 view controllers, one tied to the main view and one that is connected to the first one as a subview.

现在我们来说我的App Delegate类希望将一个字符串传递给子视图控制器。实现这一目标的最佳做法是什么？如果我想把它传递给第一个控制器，我可以这样说：

Now let's say that my App Delegate class wants to pass a string to the subview controller. What is the best practice to achieve this? If I wanted to pass it to the 1st controller i could just say something like

[self.firstController getStringInCustomFunction：[NSString stringWithFormat：@200 ％d，9]];

还请记住，此调用可能必须是异步的。

Also keep in mind that this call might have to be asynchronous.

来自ActionScript，通常我只需添加事件监听器，并通过事件移动变量。在Objective-C中相当于什么？

Coming from ActionScript, normally I would just add and event listener and move my variables though events. What's the equivalent in objective-c?

推荐答案

来自ActionScript，通常我只需添加事件侦听器并移动我的变量虽然事件。 Objective-C中的等价物是什么？

查看 NSNotificationCenter 。

具体来说， postNotificationName：object：userInfo ，其中创建 NSNotification ，其中包含一个 NSDictionary 您通过的对象 userInfo 。

另一方面，您有另一个对象是注册为听到NSNotification 的具体名称。该另一个对象调用注册中指定的任何方法。您可以在此方法中解压缩 userInfo 字典，以检索感兴趣的对象。

On the other end, you have another object that is registered to "hear" an NSNotification of a specific name. That other object calls whatever method is specified in the registration. You might unpackage the userInfo dictionary in this method, to retrieve the object of interest.

这篇关于通过Objective-C中的类传递变量的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！