我如何自定义导航返回按钮在iOS 7及以上没有标题?(即只使用箭头)

self.navigationItem.leftBarButtonItem = self.editButtonItem;

我只是想知道它们是否有self。backbuttonitem;

OR

像这样的东西?

self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]
                   initWithBarButtonSystemItem:UIBarButtonSystemItemBACK 
                   target:self action:@selector(back)];

当前回答

目标: 自定义UINavigationBar上的所有后退按钮为白色图标

步骤: 1. 在AppDelete的didFinishLaunchingWithOptions方法中:

UIImage *backBtnIcon = [UIImage imageNamed:@"navBackBtn"];


if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"7.0")) {
    [UINavigationBar appearance].tintColor = [UIColor whiteColor];
    [UINavigationBar appearance].backIndicatorImage = backBtnIcon;
    [UINavigationBar appearance].backIndicatorTransitionMaskImage = backBtnIcon;
}else{

    UIImage *backButtonImage = [backBtnIcon resizableImageWithCapInsets:UIEdgeInsetsMake(0, backBtnIcon.size.width - 1, 0, 0)];
    [[UIBarButtonItem appearance] setBackButtonBackgroundImage:backButtonImage  forState:UIControlStateNormal barMetrics:UIBarMetricsDefault];

    [[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -backButtonImage.size.height*2) forBarMetrics:UIBarMetricsDefault];
}

2.在普通超级ViewController类的viewDidLoad方法中:

 if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"7.0")) {
        UIBarButtonItem *backItem = [[UIBarButtonItem alloc] initWithTitle:@""
                                                                     style:UIBarButtonItemStylePlain
                                                                    target:nil
                                                                    action:nil];
        [self.navigationItem setBackBarButtonItem:backItem];
    }else{
        //do nothing
    }

其他回答

将标题设置为空

UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:@""  style:UIBarButtonItemStyleDone target:self action:@selector(handleBack:)];
[backButton setTintColor:Color_WHITE];
[self.navigationItem setBackBarButtonItem:backButton];

换回图像

 UIImage *backImg = [[UIImage imageNamed:@"ic_back_white"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
[UINavigationBar appearance].backIndicatorImage = backImg;
[UINavigationBar appearance].backIndicatorTransitionMaskImage = backImg;

为你的根视图控制器创建一个带有标题的UILabel,并将它分配给视图控制器的navigationItem.titleView。

现在将标题设置为空字符串,你按下一个视图控制器将有一个没有文本的返回按钮。

self.navigationItem.titleView = titleLabel; //Assuming you've created titleLabel above
self.title = @"";

你可以子类化UINavigationController,将自己设置为委托,并在委托方法navigationController:willShowViewController:animated中设置backBarButtonItem:

@interface Custom_NavigationController : UINavigationController <UINavigationControllerDelegate>

@end

@implementation Custom_NavigationController

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.delegate = self;
}

#pragma mark - UINavigationControllerDelegate

- (void)navigationController:(UINavigationController *)navigationController     willShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
    viewController.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"" style:UIBarButtonItemStylePlain target:nil action:nil];
}

@end

我找到了一个简单的方法,让我的返回按钮与iOS单箭头。

让我们假设你有一个导航控制器从ViewB到ViewA。在IB中,选择ViewA的导航栏,你应该看到这些选项:标题,提示和返回按钮。

ViewA导航栏选项

诀窍是在前一个视图控制器(view A)的选项中选择你的命运视图控制器返回按钮的标题(ViewB)。如果你不填写“返回按钮”选项,iOS将自动将标题“返回”加上前一个视图控制器的标题。因此,您需要用一个空格填充这个选项。

在“返回按钮”选项中填充空格

结果:

虽然Kyle Begeman的回答完全做到了,但在每个视图控制器中都使用这种代码是相当烦人的。我最终得到了一个简单的UINavigationItem类别。小心,这里有龙!抱歉,我的意思是:

#import <objc/runtime.h>

@implementation UINavigationItem (ArrowBackButton)

static char kArrowBackButtonKey;

+ (void)load {
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        Method m1 = class_getInstanceMethod(self, @selector(backBarButtonItem));
        Method m2 = class_getInstanceMethod(self, @selector(arrowBackButton_backBarButtonItem));
        method_exchangeImplementations(m1, m2);
    });
}

- (UIBarButtonItem *)arrowBackButton_backBarButtonItem {
    UIBarButtonItem *item = [self arrowBackButton_backBarButtonItem];
    if (item) {
        return item;
    }

    item = objc_getAssociatedObject(self, &kArrowBackButtonKey);
    if (!item) {
        item = [[UIBarButtonItem alloc] initWithTitle:@"" style:UIBarButtonItemStyleBordered target:nil action:NULL];
        objc_setAssociatedObject(self, &kArrowBackButtonKey, item, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    }
    return item;
}

@end