我在这里描述了iOS 4.2+的一个解决方案，但键盘出现后，解散按钮会消失。这并不可怕，但也不理想。

上面链接的问题中描述的解决方案包括一种更优雅的消除按钮的错觉，我将按钮淡出并垂直移动，以提供键盘和按钮一起消除的外观。

一个更简单的解决方案

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event 
{ 
    [super touchesBegan:touches withEvent:event];

    [textViewInstance1 resignFirstResponder];
    [textViewInstance2 resignFirstResponder];
    [textField resignFirstResponder];
}

如果我们告诉视图控制器的视图结束编辑，我们也可以让“user touched somewhere else”解决方案更简单:

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event 
 { 
      [super touchesBegan:touches withEvent:event];

      [self.view endEditing:YES]; //YES ignores any textfield refusal to resign
 }

．.． 假设“触摸其他地方会取消键盘”是视图中任何其他可编辑字段所期望的行为。

 let pickerView = UIPickerView()
   
 var yearpickerToolbar: UIToolbar?
   
    func createPickerView() {
          
           pickerView.delegate = self
           textfield.inputView = pickerView }
   
   
     func dismissPickerView() {
           let toolBar = UIToolbar()
           toolBar.sizeToFit()
   
           toolBar.isUserInteractionEnabled = true
           textfield.inputAccessoryView = toolBar
           textfield.delegate = self
   
   
   yearpickerToolbar = UIToolbar()
           yearpickerToolbar?.autoresizingMask = .flexibleHeight
   
           //add buttons
           let cancelButton = UIBarButtonItem(barButtonSystemItem: .cancel, target: self, action:#selector(cancelBtnClicked(_:)))
           cancelButton.tintColor = UIColor.blue
           let flexSpace = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
           
           let doneButton = UIBarButtonItem(title: "Done", style: .plain , target: self, action: #selector(self.doneBtnClicked(_ :) ))
           doneButton.tintColor = UIColor.blue
   
           doneButton.setTitleTextAttributes([NSAttributedString.Key.foregroundColor:
   UIColor.black], for: .normal)
           cancelButton.setTitleTextAttributes([NSAttributedString.Key.foregroundColor:
   UIColor.black], for: .normal)
           
           yearpickerToolbar?.items = [cancelButton, flexSpace, doneButton]
           textfield.inputAccessoryView = yearpickerToolbar }
   
   @objc func cancelBtnClicked(_ button: UIBarButtonItem?) {
           self.view.endEditing(true)
           
       }
   
       @objc func doneBtnClicked(_ button: UIBarButtonItem?) {
           self.view.endEditing(true)
       }

最简单的方法是:创建自定义透明按钮并将其放置在左下角，它将具有与UIKeyboardTypeNumberPad中的空白空间相同的CGSize。切换(显示/隐藏)这个按钮在textField成为firstresponder，按钮点击分别。

另一个解决方案。如果屏幕上有其他非数字填充文本字段，则完美。

- (void)viewDidLoad
{
    [super viewDidLoad];

    UIToolbar* numberToolbar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 50)];
    numberToolbar.barStyle = UIBarStyleBlackTranslucent;
    numberToolbar.items = @[[[UIBarButtonItem alloc]initWithTitle:@"Cancel" style:UIBarButtonItemStyleBordered target:self action:@selector(cancelNumberPad)],
                         [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil],
                         [[UIBarButtonItem alloc]initWithTitle:@"Apply" style:UIBarButtonItemStyleDone target:self action:@selector(doneWithNumberPad)]];
    [numberToolbar sizeToFit];
    numberTextField.inputAccessoryView = numberToolbar;
}

-(void)cancelNumberPad{
    [numberTextField resignFirstResponder];
    numberTextField.text = @"";
}

-(void)doneWithNumberPad{
    NSString *numberFromTheKeyboard = numberTextField.text;
    [numberTextField resignFirstResponder];
}