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)];
斯威夫特4
对于那些希望创建自定义后退按钮以及删除它们的标题的人,请在视图控制器中使用下面的一段代码来推送新的按钮:
self.navigationController?.navigationBar.backIndicatorImage = UIImage(named: "close")
self.navigationController?.navigationBar.backIndicatorTransitionMaskImage = UIImage(named: "close")
self.navigationItem?.backBarButtonItem = UIBarButtonItem(title: "", style: .plain, target: nil, action: nil)
为了更普遍的使用,请执行以下操作:
Create a universal function as follows:
func addCustomizedBackBtn(navigationController: UINavigationController?, navigationItem: UINavigationItem?) {
navigationController?.navigationBar.backIndicatorImage = UIImage(named: "close")
navigationController?.navigationBar.backIndicatorTransitionMaskImage = UIImage(named: "close")
navigationItem?.backBarButtonItem = UIBarButtonItem(title: "", style: .plain, target: nil, action: nil)
}
Then use it in the view controllers as follows:
addCustomizedBackBtn(navigationController: self.navigationController, navigationItem: self.navigationItem)
你不能以你想要的方式访问导航backButtonItem,你需要创建自己的返回按钮,如下所示:
- (void)loadView
{
[super loadView];
UIButton *backButton = [[UIButton alloc] initWithFrame: CGRectMake(0, 0, 44.0f, 30.0f)];
[backButton setImage:[UIImage imageNamed:@"back.png"] forState:UIControlStateNormal];
[backButton addTarget:self action:@selector(popVC) forControlEvents:UIControlEventTouchUpInside];
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];
}
当然了:
- (void) popVC{
[self.navigationController popViewControllerAnimated:YES];
}
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