iOS 5 [UINavigationBar外观] setBackgroundImage不起作用 [英] iOS 5 [UINavigationBar appearance] setBackgroundImage does not do work

问题描述

我在Xcode 4.2 Build 4D199中创建了一个新的测试iOS5项目，并尝试如上所述设置 UINavigationBar 的外观，但没有任何反应。

I created a new test iOS5 project in Xcode 4.2 Build 4D199 and tried to set the appearance of the UINavigationBar as described above, but nothing happens.

我在 viewDidLoad 中尝试的代码：

[[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:@"navbar-iphone.png"] forBarMetrics:UIBarMetricsDefault];

我能让它工作的唯一方法是在<$的实例上设置外观C $ C> UINavigationBar的。喜欢：

The only way I can get it to work is to set the appearance on the instance of the UINavigationBar. Like:

[self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:@"navbar-iphone.png"] forBarMetrics:UIBarMetricsDefault];

发生了什么事？还有其他人有这个问题吗？

What is going on? Has anyone else had this issue?

推荐答案

viewDidLoad 是错误的地方搞乱导航控制器导航栏的外观代理。在创建导航控制器之前执行此类操作。在你的app appate的 applicationDidFinishLaunching 是一个好地方。

viewDidLoad is the wrong place to be messing with the appearance proxy of a navigation controller's navigation bar. Do this sort of thing before the navigation controller is even created. In your app delegate's applicationDidFinishLaunching is a good place.

这篇关于iOS 5 [UINavigationBar外观] setBackgroundImage不起作用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！