子类化UINavigationBar ...如何在UINavigationController中使用它？

Question

我想子类化UINavigationBar(设置自定义背景图像和文本颜色)并将其用于我的应用程序中的所有导航栏.查看UINavigationController的API文档,看起来navigationBar是只读的:

@property(nonatomic,readonly)UINavigationBar*navigationBar

有没有办法在我的UIViewControllers中实际使用自定义UINavigationBar？我知道其他应用程序已经完成了自定义导航栏,如flickr:

http://img.skitch.com/20100520-bpxjaca11h5xne5yakjdc2m6xx.png

这是我的UINavigationBar子类:

#import <UIKit/UIKit.h>

@interface MyNavigationBar : UINavigationBar <UINavigationBarDelegate> {

}

@end

实施

#import "MyNavigationBar.h"

@implementation MyNavigationBar

- (id)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        // Initialization code
    }
    return self;
}

- (void)drawRect:(CGRect)rect {
    // override the standard background with our own custom one
    UIImage *image = [[UIImage imageNamed:@"navigation_bar_bgd.png"] retain];
    [image drawInRect:rect];
    [image release];
}

#pragma mark -
#pragma mark UINavigationDelegate Methods

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated{
    // use the title of the passed in view controller
    NSString *title = [viewController title];

    // create our own UILabel with custom color, text, etc
    UILabel *titleView = [[UILabel alloc] init];
    [titleView setFont:[UIFont boldSystemFontOfSize:18]];
    [titleView setTextColor:[UIColor blackColor]];
    titleView.text = title;
    titleView.backgroundColor = [UIColor clearColor];
    [titleView sizeToFit];

    viewController.navigationItem.titleView = titleView;
    [titleView release];

    viewController.navigationController.navigationBar.tintColor = [UIColor colorWithRed:0.1 green:0.2 blue:0.3 alpha:0.8];
}
- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated{
}


- (void)dealloc {
    [super dealloc];
}

@end

我知道我可以使用类别来更改背景图像,但我仍然希望能够设置导航栏标题的文本颜色

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

任何建议或其他解决方案？我基本上想要创建一个浅色背景和黑暗文本,如Flickr的应用程序导航栏

Answer 1

将 UINavigationBar“tint”属性设置为您想要的颜色。