我可以将图像设置为UINavigationBar的标题吗？

Question

是否可以将某些图像设置为导航栏的标题？

我认为NYTimes应用程序使用导航栏,标题看起来像图像文件(之所以看起来UINavigationBar是因为他们使用右键搜索).

Answer 1

您可以使用UIImageView该UINavigationItem.titleView财产,是这样的:

self.navigationItem.titleView = myImageView;

Answer 2

我发现高度约为35px的透明.png效果很好.

- (void)awakeFromNib {

//put logo image in the navigationBar

UIImageView* img = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"logo.png"]];
self.navigationItem.titleView = img;
[img release];

}

Answer 3

您可以从故事板(从Xcode 7开始)直接执行此操作:

1. 在视图控制器的主视图外创建视图.它可以是嵌套视图,也可以只是图像
2. 将导航项添加到视图控制器
3. 按住Ctrl键并从导航项拖动并放在外部视图上

4.选择标题视图

Answer 4

我已经为UINavigationBar创建了一个自定义类别,如下所示

UINavigationBar的+ CustomImage.h

#import <UIKit/UIKit.h>

@interface UINavigationBar (CustomImage)
    - (void) setBackgroundImage:(UIImage*)image;
    - (void) clearBackgroundImage;
    - (void) removeIfImage:(id)sender;
@end

UINavigationBar的+ CustomImage.m

#import "UINavigationBar+CustomImage.h"

@implementation UINavigationBar (CustomImage)

- (void) setBackgroundImage:(UIImage*)image {
    if (image == NULL) return;
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
    imageView.frame = CGRectMake(110,5,100,30);
    [self addSubview:imageView];
    [imageView release];
}

- (void) clearBackgroundImage {
    NSArray *subviews = [self subviews];
    for (int i=0; i<[subviews count]; i++) {
        if ([[subviews objectAtIndex:i]  isMemberOfClass:[UIImageView class]]) {
        [[subviews objectAtIndex:i] removeFromSuperview];
    }
   }    
}

@end    

我从我的UINavigationController调用它

[[navController navigationBar] performSelectorInBackground:@selector(setBackgroundImage:) withObject:image];

Answer 5

这条线对你有用,我总是用它

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

Answer 6

我修改了UINavigationBar + CustomImage.m以使标题对用户仍然可见.只需使用insertSubview:atIndex:而不是addSubview:

UINavigationBar的+ CustomImage.m

#import "UINavigationBar+CustomImage.h"

@implementation UINavigationBar (CustomImage)

- (void) setBackgroundImage:(UIImage*)image {
    if (image == NULL) return;
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
    imageView.frame = CGRectMake(0, 0, 320, 44);
    [self insertSubview:imageView atIndex:0];
    [imageView release];
}

- (void) clearBackgroundImage {
    NSArray *subviews = [self subviews];
    for (int i=0; i<[subviews count]; i++) {
        if ([[subviews objectAtIndex:i]  isMemberOfClass:[UIImageView class]]) {
        [[subviews objectAtIndex:i] removeFromSuperview];
    }
   }    
}

@end

Answer 7

这也很有效

[self.navigationController.navigationBar.topItem setTitleView:[[UIImageView alloc]initWithImage:[UIImage imageNamed:@"YourLogo"]]];