swift 自定义输入框frame、placeholder frame的textfield

/// 自定义UITextField
class JKTextField: UITextField{

/// 传入frame
var placeholderFrame:CGRect?

/// 设置placeholderframe
override func placeholderRectForBounds(bounds: CGRect) -> CGRect {
return placeholderFrame!
}

/// 设置编辑框frame
override func editingRectForBounds(bounds: CGRect) -> CGRect {
return placeholderFrame!
}

/// 文本显示的frame
override func drawTextInRect(rect: CGRect) {
super.drawTextInRect(placeholderFrame!)
}

required init(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}

/// 自定义初始化方法，传入frame
init (frame:CGRect ,placeholderFrame:CGRect){
self.placeholderFrame = placeholderFrame
super.init(frame: frame)
self.returnKeyType = .Done
}
}