Improve keyboard observers handle
Improve keyboard observers handle

yizzuide/SCLAlertView,wintersweet/SCLAlertView,yatryan/SCLAlertView,dogo/SCLAlertView,gudjao/SCLAlertView,hoanganh6491/SCLAlertView,sprylogics/SCLAlertView,brucec5/SCLAlertView,dogo/SCLAlertView,imhome/SCLAlertView,brunov0id/SCLAlertView,mdimarca/SCLAlertView,sunzeboy/SCLAlertView,icepy/SCLAlertView,HuylensHu/SCLAlertView,n1mda/SCLAlertView,mbelkin/SCLAlertView,dogo/SCLAlertView,ThibaultKlein/SCLAlertView,alecgorge/SCLAlertView,leleks/SCLAlertView,bfeher/SCLAlertView