导航
[self.navigationController.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault]; [self.navigationController.navigationBar setShadowImage:[UIImage new]];


导航透明设置

  [self.navigationController.navigationBar setTranslucent:NO];


tab
[self.tabBarController.tabBar setBackgroundImage:[UIImage new]];
[self.tabBarController.tabBar setShadowImage:[UIImage new]];