您可以使用块通过更好的方法来实现这一点:
class MyTextField: UITextField, UITextFieldDelegate {
//MARK:- PROPERTIES
var shouldPreventAllActions:Bool = false
var canCut:Bool = true
var canCopy:Bool = true
var canPaste:Bool = true
var canSelect:Bool = true
var canSelectAll:Bool = true
var blockTextFieldShouldChangeCharactersInRangeWithReplacementString:((_ textField: UITextField, _ range: NSRange, _ string: String) -> Bool)?
var blockTextFieldShouldReturn:((_ textField: UITextField) -> Bool)?
var blockTextFieldShouldClear:((_ textField: UITextField) -> Bool)?
//MARK:-
var blockTextFieldShouldBeginEditing:((_ textField: UITextField) -> Bool)?
var blockTextFieldShouldEndEditing:((_ textField: UITextField) -> Bool)?
//MARK:-
var blockTextFieldDidBeginEditing:((_ textField: UITextField) -> Void)?
var blockTextFieldDidEndEditing:((_ textField: UITextField) -> Void)?
var blockTextFieldDidEndEditingWithReason:((_ textField: UITextField, _ reason: UITextFieldDidEndEditingReason) -> Void)?
//MARK:- INIT
override init(frame: CGRect) {
super.init(frame: frame)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override func awakeFromNib() {
super.awakeFromNib()
commonInit()
}
private func commonInit(){
// common initialization code..
}
override func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
if(self.shouldPreventAllActions){
return false
}
switch action {
case #selector(UIResponderStandardEditActions.cut(_:)):
return self.canCut ? super.canPerformAction(action, withSender: sender) : self.canCut
case #selector(UIResponderStandardEditActions.copy(_:)):
return self.canCopy ? super.canPerformAction(action, withSender: sender) : self.canCopy
case #selector(UIResponderStandardEditActions.paste(_:)):
return self.canPaste ? super.canPerformAction(action, withSender: sender) : self.canPaste
case #selector(UIResponderStandardEditActions.select(_:)):
return self.canSelect ? super.canPerformAction(action, withSender: sender) : self.canSelect
case #selector(UIResponderStandardEditActions.selectAll(_:)):
return self.canSelectAll ? super.canPerformAction(action, withSender: sender) : self.canSelectAll
default:
return super.canPerformAction(action, withSender: sender)
}
}
//MARK:- DELEGATE
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
if(self.blockTextFieldShouldChangeCharactersInRangeWithReplacementString != nil){
return self.blockTextFieldShouldChangeCharactersInRangeWithReplacementString!(textField,range,string)
}else{
return true
}
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
if(self.blockTextFieldShouldReturn != nil){
return self.blockTextFieldShouldReturn!(textField)
}else{
return true
}
}
func textFieldShouldClear(_ textField: UITextField) -> Bool {
if(self.blockTextFieldShouldClear != nil){
return self.blockTextFieldShouldClear!(textField)
}else{
return true
}
}
//MARK:-
func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
if(self.blockTextFieldShouldBeginEditing != nil){
return self.blockTextFieldShouldBeginEditing!(textField)
}else{
return true
}
}
func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {
if(self.blockTextFieldShouldEndEditing != nil){
return self.blockTextFieldShouldEndEditing!(textField)
}else{
return true
}
}
//MARK:-
func textFieldDidBeginEditing(_ textField: UITextField) {
if(self.blockTextFieldDidBeginEditing != nil){
self.blockTextFieldDidBeginEditing!(textField)
}
}
func textFieldDidEndEditing(_ textField: UITextField) {
if(self.blockTextFieldDidEndEditing != nil){
self.blockTextFieldDidEndEditing!(textField)
}
}
func textFieldDidEndEditing(_ textField: UITextField, reason: UITextFieldDidEndEditingReason) {
if(self.blockTextFieldDidEndEditingWithReason != nil){
self.blockTextFieldDidEndEditingWithReason!(textField,reason)
}
}
}