ios - UINaviationItem 中的 UIToolbar 顶部有奇怪的行

Question

我试图通过以下方式在 UINavigationItem 的 titleView 中显示一个 UIToolbar:

UIBarButtonItem *mapItem = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"world_icon"]
                                                            style:UIBarButtonItemStylePlain
                                                           target:self action:@selector(hi)];
UIBarButtonItem *mapItem2 = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"world_icon"]
                                                            style:UIBarButtonItemStylePlain
                                                           target:self action:@selector(hi)];
UIBarButtonItem *spaceItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
UIToolbar *toolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 320, 44)];

toolbar.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
[toolbar setItems:@[mapItem, spaceItem, mapItem2, spaceItem]];
toolbar.backgroundColor = [UIColor clearColor];
toolbar.barStyle = UIBarStyleDefault;
[toolbar setBackgroundImage:[UIImage new]
              forToolbarPosition:UIBarPositionAny
                      barMetrics:UIBarMetricsDefault];
toolbar.tintColor = [UIColor whiteColor];

self.navigationItem.titleView = toolbar;

但是我在工具栏顶部看到了这条奇怪的黑线:

知道是什么原因造成的吗？谢谢!

Answer 1

我不知道这是怎么回事，但我遇到了和你一样的问题，我在使用中修复了它

toolbar.clipsToBounds = YES 

你也可以试试下面的
或

[[UINavigationBar appearance] setBackgroundImage:[[UIImage alloc] init]
                                  forBarPosition:UIBarPositionAny
                                      barMetrics:UIBarMetricsDefault];

[[UINavigationBar appearance] setShadowImage:[[UIImage alloc] init]];