How to dismiss keyboard when user tap other area outside textfield?

How to dismiss keyboard when user tap other area outside textfield?

today I tried to run my code on my iPod (iOS 6.1.3) and I found something
interesting here...
first, when I tap on textfield the keyboard shows up but it won't hide
when I tap somewhere else outside textfield.
so I decided to Googling and found this solution :
_fieldEmail.delegate = self;
_fieldEmail.returnKeyType = UIReturnKeyDone;
_fieldPassword.delegate = self;
_fieldPassword.returnKeyType = UIReturnKeyDone;
_fieldRegisterName.delegate = self;
_fieldRegisterName.returnKeyType = UIReturnKeyDone;
_fieldRegisterEmail.delegate = self;
_fieldRegisterEmail.returnKeyType = UIReturnKeyDone;
_fieldRegisterPassword.delegate = self;
_fieldRegisterPassword.returnKeyType = UIReturnKeyDone;
it works... it gives a 'DONE' button on the bottom of keyboard and now the
keyboard can be hidden by pressing it.
but I have 2 problems here :
the keyboard only hide when 'DONE' button is tapped. not by tapping other
area outside text field. I don't know if this normal on iOS world, but
usually I see lot of apps don't act like this.
is there any way to loop this process so I don't have manually add that
delegate one by one of all textfield that I have? how to do that?
that's all I need to know , thank you...