先presentModalViewController后pushViewController没有效果的解决方法

在做项目的时候，先用presentModalViewController到登录界面，在登录界面在pushViewController到注册界面，push不过去。

LoginViewController *login = [[LoginViewController alloc]init];  [self.navigationController presentModalViewController:login animated:YES];  //在LoginViewController中push到RegisterViewController没有效果  RegisterViewController *registerViewConotroller = [[RegisterViewController alloc]init];   [self.navigationController pushViewController:registerViewConotroller animated:YES];  

解决办法，在presentModalViewController的时候加上UINavigationController，就可以了，如下:

LoginViewController *login = [[LoginViewController alloc]init];  UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:login];  [self.navigationController presentModalViewController:nav animated:YES];