覆盖 navigationController 的 navigationBar 属性的最佳点 [英] Best point to overwrite the navigationBar property of navigationController

问题描述

我正在覆盖 UINavigationController 以使用我自己的 UINavigationBar 子类的实例替换默认的 navigationBar 属性.所以我尝试了类似

I'm overwriting UINavigationController to replace the default navigationBar property with an instance of my own subclass of UINavigationBar. So I tried something like

_navigationBar = [[SBNavigationBar alloc] init];

在我的 -initWithRootViewController: 中.但这并没有像我预期的那样成功.仍然显示默认的 navigationBar.

in my -initWithRootViewController:. But that didn't work out as I expected it. There's still the default navigationBar being displayed.

那么覆盖 navigationBar 的最佳点是什么?

So what's the best point to overwrite the navigationBar?

提前致谢
-f

推荐答案

如果你查看文档 http://developer.apple.com/iphone/library/documentation/uikit/reference/UINavigationController_Class/Reference/Reference.html，你会看到navigationBar 属性是只读.

If you check the documentation http://developer.apple.com/iphone/library/documentation/uikit/reference/UINavigationController_Class/Reference/Reference.html, you'll see that the navigationBar property is read-only.

要自定义 navigationBar，您可以使用 Categories.您会在 stackoverflow 上找到许多问题的答案.

To have a custom navigationBar you can use Categories for example. You will find many questions answering this here on stackoverflow.

一个简单的版本是将图像放入 drawRect: 就像这样......

One simple version is putting an image in drawRect: like so...

@implementation UINavigationBar (Custom)

- (void)drawRect:(CGRect)rect {
    UIImage *image = [UIImage imageNamed: @"bg_toolbar.png"];
    [image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}

@end

这篇关于覆盖 navigationController 的 navigationBar 属性的最佳点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！