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)];
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
如果你设置了导航栏的tintColor,添加一个没有标题的自定义后退按钮图像,该图像的tintColor将反映图像的颜色。请点击苹果文档链接。
https://developer.apple.com/library/content/documentation/UserExperience/Conceptual/UIKitUICatalog/index.html#//apple_ref/doc/uid/TP40012857-UIView-SW7
UINavigationItem *navItem = [[UINavigationItem alloc] init];
navBar.tintColor = self.tintColor;
UIImage *myImage = [UIImage imageNamed:@"left_arrow.png"];
myImage = [myImage imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
UIBarButtonItem *leftButton = [[UIBarButtonItem alloc] initWithImage:myImage style:UIBarButtonItemStylePlain target:self action:@selector(cancelButtonFunction:)];
navItem.leftBarButtonItem = leftButton;
navBar.items = @[ navItem ];
在你的第一个ViewController的prepareForSegue:方法中,你设置视图标题为@"",所以当下一个视图被推送时,它将显示前一个ViewController标题为@""。
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
self.navigationItem.title = @" ";
}
唯一的问题是,当你点击返回按钮时,你之前的视图将没有标题,所以你可以在viewWillAppear上再次添加它:
-(void)viewWillAppear:(BOOL)animated{
self.navigationItem.title = @"First View Title";
}
我不太喜欢这个解决方案,但它是可行的,我没有找到其他方法来做到这一点。
如果你有两个ViewController(FirstVC, seconddvc)嵌入在导航控制器中,你想在seconddvc中只有后退箭头。
你可以试试这个
在FirstVC的ViewDidLoad中
override func viewDidLoad() {
super.viewDidLoad()
self.navigationItem.backBarButtonItem = UIBarButtonItem(title: "", style: .Plain, target: nil, action: nil)
}
然后当你推到seconddvc,你会看到只有后退箭头