仅使用 iPhone OS 3.2 类
您将如何编写一个使用 iPhone OS 3.2 中引入的类（例如 UIPopoverController 和 UISplitViewController）的通用应用程序？在 Jeff LaMarche 的博客中，Ole 提供了一种实例化这些对象的方法；您可以像这样实例化一个 UIPopoverController：[NSClassFromString(@"UIPopoverController") alloc]。
这对于在代码中实例化这些类来说很好，但是协议及其方法呢？我的 iPad 应用程序使用 UISplitViewController 并有一个需要符合 UISplitViewControllerDelegate 和 UIPopoverControllerDelegate 的类。你会如何声明这一点？您将如何使用如下方法？
- (void)splitViewController:(UISplitViewController *)svc willHideViewController:(UIViewController *)aViewController withBarButtonItem:(UIBarButtonItem *)barButtonItem forPopoverController:(UIPopoverController *)pc
其中方法调用需要传入 UISplitViewController ？
How would you write a universal app that uses classes introduced in iPhone OS 3.2, such as UIPopoverController and UISplitViewController? On Jeff LaMarche's blog about this, Ole provides a method for instantiating these objects; you would instantiate a UIPopoverController like so: [NSClassFromString(@"UIPopoverController") alloc].
This is fine for instantiating these classes in code but what about protocols and their methods? My iPad app uses a UISplitViewController and has a class that needs to conform to the UISplitViewControllerDelegate and UIPopoverControllerDelegate. How would you declare this? And how would you work with a method such as the following?
- (void)splitViewController:(UISplitViewController *)svc
willHideViewController:(UIViewController *)aViewController
withBarButtonItem:(UIBarButtonItem *)barButtonItem
forPopoverController:(UIPopoverController *)pc
where the method call requires UISplitViewController to be passed in?
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（2）
您可以将其保留在那里，因为这些
UISplitViewController*等仅充当编译器进行类型检查的类型（与实际符号需要的[UISplitViewController alloc]不同）被链接）。如果无法编译，请在文件开头添加
@class UISplitViewController, UIPopoverController;。You can leave it there, since these
UISplitViewController*etc only serves as a type for the compiler to do type-checking (unlike[UISplitViewController alloc]which an actual symbol needs to be linked).Add a
@class UISplitViewController, UIPopoverController;at the start of the file if it doesn't compile.而且，就像这样，我发现如果您弱链接 UIKit 框架，这不是问题。我在 Stack Overflow 上找到了这个。
And, just like that, I see that this isn't a problem if you weak-link the UIKit framework. I found this right here on Stack Overflow.