UIAlertController使用addTextFieldWithConfigurationHandler

UIAlertController 中 使用addTextFieldWithConfigurationHandler进行文本框的输入但是确认或取消后键盘收起的速度太慢，如何解决？？

• (void)buttonAction {

  UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert];
  
  [alert addAction:[UIAlertAction actionWithTitle:@"OK"
                                            style:UIAlertActionStyleDefault
                                          handler:^(UIAlertAction *action) {
                                              NSLog(@"OK pushed");
  
                                          }]];
  
  [alert addTextFieldWithConfigurationHandler:^(UITextField *textField) {
      textField.placeholder = @"text input";
      textField.delegate = self;
  }];
  
  [self presentViewController:alert animated:YES completion:nil];

  }