自定义UITabBar 在 popToViewController 或popToRootViewController后UITabBarItem出现重叠

-(void)viewWillLayoutSubviews{    [super viewWillLayoutSubviews];     for (UIView *child in self.tabBar.subviews) {        if ([child isKindOfClass:NSClassFromString(@"UITabBarButton")]) {            [child removeFromSuperview];        }    }}- (void)viewWillAppear:(BOOL)animated{    [super viewWillAppear:animated];    // 删除系统自动生成的UITabBarButton    for (UIView *child in self.tabBar.subviews) {        if ([child isKindOfClass:[UIControl class]]) {            [child removeFromSuperview];        }    }}