ios去掉navigationController和tabBarController裡的邊框黑線

- (void)viewWillAppear:(BOOL)animated {
    [self.navigationController.navigationBar setBackgroundImage:[TDUtils createImageWithColor:[UIColor clearColor]] forBarMetrics:UIBarMetricsDefault];
    [self.navigationController.navigationBar setBackIndicatorTransitionMaskImage:[TDUtils createImageWithColor:[UIColor clearColor]]];
    [self.navigationController.navigationBar setShadowImage:[TDUtils createImageWithColor:[UIColor clearColor]]];
    
    [self.tabBarController.tabBar setBackgroundImage:[TDUtils createImageWithColor:[UIColor clearColor]]];
    [self.tabBarController.tabBar setShadowImage:[TDUtils createImageWithColor:[UIColor clearColor]]];
}