重载 UINavigationController 设置左侧返回按钮的文字为图片

UINavigationController

导航栏控制器的左侧返回按钮如果需要设置成图片,仅使用系统的是无法实现的,需要重载系统的导航栏控制器,在控制器推出之前替换掉leftBarButtonItem才行.

注:以下链接的这个哥们对NavigationViewController所有能做的定制都解说了

http://beyondvincent.com/blog/2013/11/03/120-customize-navigation-status-bar-ios-7/#5

源码如下:

CustomNavigationViewController.h + CustomNavigationViewController.m

 

#import <UIKit/UIKit.h>



@interface CustomNavigationViewController : UINavigationController



@end

 

#import "CustomNavigationViewController.h"



#pragma mark - 支持ARC与非ARC

#if __has_feature(objc_arc)

#define RELEASE(obj)

#define AUTO_RELEASE(obj)

#else

#define Release(obj)      [obj release]

#define Autorelease(obj)  [obj autorelease]

#endif



//判断是否是iOS7

#define iOS7 \

([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0)



@interface CustomNavigationViewController ()



@end



@implementation CustomNavigationViewController



#pragma mark - 重载父类进行改写

- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated

{

    //先进入子Controller

    [super pushViewController:viewController animated:animated];

    

    //替换掉leftBarButtonItem

    if (viewController.navigationItem.leftBarButtonItem== nil && [self.viewControllers count] > 1) {

        viewController.navigationItem.leftBarButtonItem =[self customLeftBackButton];

    }

}



#pragma mark - 自定义返回按钮图片

-(UIBarButtonItem*)customLeftBackButton{

    

    UIImage *image = [UIImage imageNamed:@"back.png"];

    

    UIButton *backButton = [UIButton buttonWithType:UIButtonTypeCustom];

    

    backButton.frame = CGRectMake(0, 0, image.size.width, image.size.height);

    

    [backButton setBackgroundImage:image

                          forState:UIControlStateNormal];

    

    [backButton addTarget:self

                   action:@selector(popself)

         forControlEvents:UIControlEventTouchUpInside];

    

    UIBarButtonItem *backItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];

    Autorelease(backItem);

    

    return backItem;

}



#pragma mark - 返回按钮事件(pop)

-(void)popself

{

    [self popViewControllerAnimated:YES];

}



#pragma mark - 用图片设置导航背景

+ (void)initialize

{

    //取出设置主题的对象

    UINavigationBar *navBar = [UINavigationBar appearance];

    

    //设置导航栏的背景图片

    NSString *navBarBg = nil;

    if (iOS7)

    {

        navBarBg = @"NavBar64";

        navBar.tintColor = [UIColor whiteColor];

    }

    else

    {

        navBarBg = @"NavBar";

        [UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleLightContent;

    }

    [navBar setBackgroundImage:[UIImage imageNamed:navBarBg] forBarMetrics:UIBarMetricsDefault];

    

    //标题颜色

    [navBar setTitleTextAttributes:@{NSForegroundColorAttributeName : [UIColor whiteColor]}];

}



@end