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)];
iOS7有新的界面规则,所以当你推送一个UIView时,最好至少保留后退箭头。
通过编程方式更改“返回”文本非常容易。只需要在推送视图之前添加这段代码(如果你使用的是StoryBoards,可以使用prepareForSegue):
-(void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
self.navigationItem.backBarButtonItem=[[UIBarButtonItem alloc] initWithTitle:@"NEW TITLE" style:UIBarButtonItemStylePlain target:nil action:nil];
}
这将改变默认的“后退”文本,但将保持iOS7风格的后退箭头。
你也可以在推送视图之前改变后退箭头的颜色:
- (void)viewDidLoad{
//NavBar background color:
self.navigationController.navigationBar.barTintColor=[UIColor redColor];
//NavBar tint color for elements:
self.navigationController.navigationBar.tintColor=[UIColor whiteColor];
}
希望这对你有所帮助!
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
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
}
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。