iOS导航栏的正确隐藏方式(解决右滑返回上一层页面时导航栏出现空白的问题)
iOS导航栏的正确隐藏方式(解决右滑返回上一层页面时导航栏出现空白的问题)
第一种做法用动画的方式隐藏导航栏,这样在使用滑动返回手势的时候效果最好，这样做有一个缺点就是在切换tabBar的时候有一个导航栏向上消失的动画.
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[self.navigationController setNavigationBarHidden:YES animated:animated];
}
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
[self.navigationController setNavigationBarHidden:NO animated:animated];
}
第二种做法设置self为导航控制器的代理,实现代理方法,在将要显示控制器中设置导航栏隐藏和显示,使用这种方式不仅完美切合滑动返回手势,同时也解决了切换tabBar的时候,导航栏动态隐藏的问题。最后要记得在控制器销毁的时候把导航栏的代理设置为nil。
@interface HomeViewController ()
@end
@implementation HomeViewController
- (void)viewDidLoad {
[super viewDidLoad];
// 设置导航控制器的代理为self
self.navigationController.delegate = self;
}
#pragma mark - UINavigationControllerDelegate
// 将要显示控制器
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
// 判断要显示的控制器是否是要隐藏的控制器
BOOL isHome = [viewController isKindOfClass:[self class]];
[self.navigationController setNavigationBarHidden:isHome animated:YES];
}
- (void)dealloc {
self.navigationController.delegate = nil;
}
第三种做法
主要是针对A隐藏Nav, A push 到B，B也需要隐藏Nav的这种情况 主要是在自定义UINavigationController文件内进行操作的
自定义UINavigationController
#import "NavigationController.h"
#import "HomeViewController.h"
#import "HomeViewController_two.h"
@interface NavigationController ()
@end
@implementation NavigationController
- (void)viewDidLoad {
[super viewDidLoad];
self.delegate = self;
// 设置全屏滑动返回
id target = self.interactivePopGestureRecognizer.delegate;
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:target action:@selector(handleNavigationTransition:)];
[self.view addGestureRecognizer:pan];
self.interactivePopGestureRecognizer.enabled = NO;
}
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated{
if (self.viewControllers.count > 0) {
viewController.hidesBottomBarWhenPushed = YES;
}
[super pushViewController:viewController animated:animated];
}
#pragma mark - UINavigationControllerDelegate
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
// 判断如果是需要隐藏导航控制器的类，则隐藏
BOOL isHideNav = ([viewController isKindOfClass:[HomeViewController class]] ||
[viewController isKindOfClass:[HomeViewController_two class]]);
//setNavigationBarHidden:YES设置这行代码后会导致Nav的滑动返回手势失效，这也就是为什么前面我们在自定义导航的时候需要设置全屏滑动返回了
[self setNavigationBarHidden:isHideNav animated:YES];
}