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
斯威夫特
斯威夫特4.2
textfield.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)), for: .editingChanged)
and
@objc func textFieldDidChange(_ textField: UITextField) {
}
SWIFT 3和SWIFT 4.1
textField.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)), for: .editingChanged)
and
func textFieldDidChange(_ textField: UITextField) {
}
斯威夫特2.2
textField.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)), forControlEvents: UIControlEvents.EditingChanged)
and
func textFieldDidChange(textField: UITextField) {
//your code
}
objective - c
[textField addTarget:self action:@selector(textFieldDidChange:) forControlEvents:UIControlEventEditingChanged];
和textFieldDidChange方法是
-(void)textFieldDidChange :(UITextField *) textField{
//your code
}
其他回答
您可以在接口生成器中建立此连接。
在故事板中，单击屏幕顶部的助理编辑器(中间的两个圆圈)。 在界面构建器中按Ctrl +单击文本字段。 从EditingChanged拖动到助手视图中的视图控制器类内部。 为函数命名(例如“textDidChange”)，然后单击连接。
斯威夫特
斯威夫特4.2
textfield.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)), for: .editingChanged)
and
@objc func textFieldDidChange(_ textField: UITextField) {
}
SWIFT 3和SWIFT 4.1
textField.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)), for: .editingChanged)
and
func textFieldDidChange(_ textField: UITextField) {
}
斯威夫特2.2
textField.addTarget(self, action: #selector(ViewController.textFieldDidChange(_:)), forControlEvents: UIControlEvents.EditingChanged)
and
func textFieldDidChange(textField: UITextField) {
//your code
}
objective - c
[textField addTarget:self action:@selector(textFieldDidChange:) forControlEvents:UIControlEventEditingChanged];
和textFieldDidChange方法是
-(void)textFieldDidChange :(UITextField *) textField{
//your code
}
斯威夫特4
在viewDidLoad ():
//ADD BUTTON TO DISMISS KEYBOARD
// Init a keyboard toolbar
let toolbar = UIView(frame: CGRect(x: 0, y: view.frame.size.height+44, width: view.frame.size.width, height: 44))
toolbar.backgroundColor = UIColor.clear
// Add done button
let doneButt = UIButton(frame: CGRect(x: toolbar.frame.size.width - 60, y: 0, width: 44, height: 44))
doneButt.setTitle("Done", for: .normal)
doneButt.setTitleColor(MAIN_COLOR, for: .normal)
doneButt.titleLabel?.font = UIFont(name: "Titillium-Semibold", size: 13)
doneButt.addTarget(self, action: #selector(dismissKeyboard), for: .touchUpInside)
toolbar.addSubview(doneButt)
USDTextField.inputAccessoryView = toolbar
增加这个函数:
@objc func dismissKeyboard() {
//Causes the view (or one of its embedded text fields) to resign the first responder status.
view.endEditing(true)
}
现在在iOS13+上有一个UITextField委托方法可用
optional func textFieldDidChangeSelection(_ textField: UITextField)
斯威夫特4
符合 UITextFieldDelegate。
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
// figure out what the new string will be after the pending edit
let updatedString = (textField.text as NSString?)?.replacingCharacters(in: range, with: string)
// Do whatever you want here
// Return true so that the change happens
return true
}
