Change the text and arrow color of the left navigation bar after the iOS page jumps_html/css_WEB-ITnose

 LoginViewController *loginViewController  =[[ LoginViewController alloc] init];
                UINavigationController *nav=[[UINavigationController alloc]initWithRootViewController:loginViewController];
                

                UIButton *leftBtn = [UIButton buttonWithType:UIButtonTypeCustom];

                leftBtn.frame = CGRectMake(0, 0, 70, 37);
                leftBtn.titleLabel.font=[UIFont systemFontOfSize:25.0];
                [leftBtn setTitle:@"取消" forState:UIControlStateNormal];
                [leftBtn addTarget:self action:@selector(dismissController) forControlEvents:UIControlEventTouchUpInside];
                
                loginViewController.navigationItem.leftBarButtonItem =[[UIBarButtonItem alloc] initWithCustomView:leftBtn];
                [self.navigationController presentViewController:nav animated:YES completion:nil];

更改箭头颜色：
self.navigationController.navigationBar.tintColor = [UIColor whiteColor];