// 控制台错误
2016-07-12 17:54:30.627 Floral[45403:1375185] Presenting view controllers on detached view controllers is discouraged <Floral.LoginViewController: 0x7fff0a59b880>.
2016-07-12 17:54:32.271 Floral[45403:1375185] Warning: Attempt to present <Floral.NavgationViewController: 0x7fff0a964400> on <Floral.LoginViewController: 0x7fff0a69a0b0> whose view is not in the window hierarchy!
