如何处理iOS 11导航BarButtonItems错误？
我在iOS 11中发现了一个UINavigationBar错误。使用self.navigationItem.rightBarButtonItems = @[fixSpaceItem, item]在viewDidLoad中快速设置导航项按钮。 然后使用手势回弹，但我没有回弹，当弹出回来时，我释放手指并让视图控制器取消弹回，然后右侧导航按钮项目消失。 左项按钮具有相同的问题。 要重现此错误，您必须添加fixSpaceItem，如[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil] 。 而真正的设备，但不是模拟器可以重现错误。 这是我的主要代码：
- (void)viewDidLoad { [super viewDidLoad]; self.navigationController.interactivePopGestureRecognizer.enabled = YES; self.navigationController.interactivePopGestureRecognizer.delegate = self; self.navigationItem.rightBarButtonItems = @[[self negativeSpacerWithWidth:5],[self rightButton]]; self.navigationItem.leftBarButtonItems = @[[self negativeSpacerWithWidth:5], [self leftButton]]; } - (UIBarButtonItem *)leftButton { UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 35, 35)]; [button setImage:[UIImage imageNamed:@"icon_app_back_normal"] forState:UIControlStateNormal]; [button addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside]; UIBarButtonItem *item = [[UIBarButtonItem alloc] initWithCustomView:button]; return item; } - (UIBarButtonItem *)rightButton { UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 35, 35)]; [button setImage:[UIImage imageNamed:@"setting"] forState:UIControlStateNormal]; UIBarButtonItem *item = [[UIBarButtonItem alloc] initWithCustomView:button]; return item; } - (UIBarButtonItem *)negativeSpacerWithWidth:(CGFloat)width { UIBarButtonItem *spacer = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil]; [spacer setWidth:width]; return spacer; }
将FixedSpace BarButtonItem添加到BarButtonItem array时，这似乎是一个错误。 如果要将偏移设置为导航项，可能必须使用其他方式，例如更改按钮的imageEdgeInsets。
- (void)viewDidLoad { [super viewDidLoad]; // Do not set Fixed Space type button item. self.navigationItem.leftBarButtonItem = [self leftButton]; self.navigationItem.rightBarButtonItem = [self rightButton]; // It work too //self.navigationItem.leftBarButtonItems = @[[self leftButton], [self leftButton]]; //self.navigationItem.rightBarButtonItems = @[[self rightButton], [self rightButton]]; self.navigationController.interactivePopGestureRecognizer.enabled = YES; self.navigationController.interactivePopGestureRecognizer.delegate = self; } - (UIBarButtonItem *)leftButton { UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 35, 35)]; //... // to add offset you want button.imageEdgeInsets = UIEdgeInsetsMake(0, -15, 0, 15); UIBarButtonItem *item = [[UIBarButtonItem alloc] initWithCustomView:button]; return item; } - (UIBarButtonItem *)rightButton { UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 35, 35)]; //... // to add offset you want button.imageEdgeInsets = UIEdgeInsetsMake(0, 15, 0, -15); UIBarButtonItem *item = [[UIBarButtonItem alloc] initWithCustomView:button]; return item; }
我尝试调整图像大小以使其适合导航项目并且它有效。 虽然您不需要实际调整图像大小，但可以使用下面提供的函数在运行时调整Image的大小。
UIImage *imgCart = [self imageWithImage:[UIImage imageNamed:@"ic_cart"] scaledToSize:CGSizeMake(35, 35)] ; UIButton *btnCart = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 30, 30)]; [btnCart addTarget:self action:@selector(btnCartClicked:) forControlEvents:UIControlEventTouchUpInside]; [btnCart setBackgroundImage:imgCart forState:UIControlStateNormal]; self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:btnCart]; -(UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize { //UIGraphicsBeginImageContext(newSize); // In next line, pass 0.0 to use the current device's pixel scaling factor (and thus account for Retina resolution). // Pass 1.0 to force exact pixel size. UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0); [image drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)]; UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return newImage; }
let hamButtonWidthConstraint = hamButton.widthAnchor.constraint(equalToConstant: 40) let hamButtonHeightConstraint = hamButton.heightAnchor.constraint(equalToConstant: 40) hamButtonWidthConstraint.isActive = true hamButtonHeightConstraint.isActive = true