Swift --下一响应者

var nextRes = self.nextResponder()! as UIResponder
repeat{
//
if ((nextRes.isKindOfClass(UITextView))){

let t = nextRes as! UITextView
t.resignFirstResponder()
t.text = ""
return
}
if(nextRes.isKindOfClass(UITextField)){
let t = nextRes as! UITextField
t.text = ""
t.resignFirstResponder()
return
}
nextRes = nextRes.nextResponder()!
}while(true)

var nextRes = self.nextResponder()

while(nextRes != nil){
if(nextRes!.isKindOfClass(UITextView)){
let root = nextRes as! UITextView
root.resignFirstResponder()
return
}

if(nextRes!.isKindOfClass(UITextField)){
let root = nextRes as! UITextField
root.resignFirstResponder()
return
}

nextRes = nextRes?.nextResponder()

}