void OnEnable()
 {
     s_Instance           = this;
     m_TipLabel.text      = "";
     m_TipLabel.color     = new Color(1, 1, 1, 0);
     m_WarningLabel.text  = "";
     m_WarningLabel.color = new Color(1, 0, 0, 0);
     m_TipAliveTime       = 0f;
     m_Warnings           = new List <string> ();
 }
 void OnDestroy()
 {
     s_Instance = null;
 }