我试图检查当一个文本字段发生变化时，等效于textView - textViewDidChange的函数，到目前为止我已经做到了这一点:
func textFieldDidBeginEditing(textField: UITextField) {
if self.status.text == "" && self.username.text == "" {
self.topRightButton.enabled = false
} else {
self.topRightButton.enabled = true
}
}
哪种类型的工作，但topRightButton一经文本字段被按下就被启用，我想它只在文本实际输入时才被启用?
当前回答
Swift 3.0.1+(其他一些Swift 3.0的答案不是最新的)
textField.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)),
for: UIControlEvents.editingChanged)
func textFieldDidChange(_ textField: UITextField) {
}
其他回答
Swift 3.0.1+(其他一些Swift 3.0的答案不是最新的)
textField.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)),
for: UIControlEvents.editingChanged)
func textFieldDidChange(_ textField: UITextField) {
}
斯威夫特4
textField.addTarget(self, action: #selector(textIsChanging), for: UIControlEvents.editingChanged)
@objc func textIsChanging(_ textField:UITextField) {
print ("TextField is changing")
}
如果你想在用户完全输入后进行更改(一旦用户退出键盘或按enter键，它将被调用)。
textField.addTarget(self, action: #selector(textDidChange), for: UIControlEvents.editingDidEnd)
@objc func textDidChange(_ textField:UITextField) {
print ("TextField did changed")
}
txf_Subject.addTarget(self, action:#selector(didChangeFirstText), for: .editingChanged)
@objc func didChangeText(textField:UITextField) {
let str = textField.text
if(str?.contains(" "))!{
let newstr = str?.replacingOccurrences(of: " ", with: "")
textField.text = newstr
}
}
@objc func didChangeFirstText(textField:UITextField) {
if(textField.text == " "){
textField.text = ""
}
}
你可以通过“shouldchangecharter”委托或者“begin and end”文本字段委托来管理编辑。别忘了设置委托
我设法做到这一点使用“did开始和结束编辑”下面。
//MARK:- TextViewDelegate
extension ViewController: UITextFieldDelegate {
func textFieldDidEndEditing(_ textField: UITextField) {
let count = self.tfEmail.text?.count ?? 0
if textField == self.tfEmail {
if count == 0{
//Empty textfield
}else{
//Non-Empty textfield
}
}
}
func textFieldDidBeginEditing(_ textField: UITextField) {
if textField == self.tfEmail{
//when user taps on textfield
}
}
}
这是如何使用Swift 3添加textField文本更改监听器:
将你的类声明为UITextFieldDelegate
override func viewDidLoad() {
super.viewDidLoad()
textField.delegate = self
textField.addTarget(self, action: #selector(UITextFieldDelegate.textFieldShouldEndEditing(_:)), for: UIControlEvents.editingChanged)
}
然后只是传统地添加一个textFieldShouldEndEditing函数:
func textFieldShouldEndEditing(_ textField: UITextField) -> Bool { // do stuff
return true
}
