ios - UILongPressGestureRecognizer 在文本字段上显示警报

Question

我有一个 UILongPressGestureRecognizer 添加到 UITextField。当我按下 UITextField 时，它会显示警报，但这是三个警报显示。那是我的代码：

- (void)viewDidLoad
{
    [super viewDidLoad];
    UILongPressGestureRecognizer *gs = [[UILongPressGestureRecognizer      alloc]initWithTarget:self action:@selector(AlertServer:)];
    gs.delegate = self;
    [_companyidTxt addGestureRecognizer:gs];
    [gs release];
}
-(void)AlertServer:(UILongPressGestureRecognizer *)gs
{
    alertView = [[UIAlertView alloc] initWithTitle:@"Server" message:@"" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Okay", nil];
    alertView.alertViewStyle = UIAlertViewStylePlainTextInput;
    myTextField = [alertView textFieldAtIndex:0];
    myTextField.text=mainString;
    [alertView show];
    [alertView release];
    [alertView retain];
}

谁能解释为什么会发生这种情况，以及如何预防？提前感谢

Answer 1

试试这个，

-  (void)AlertServer:(UILongPressGestureRecognizer*)sender { 
    if (sender.state == UIGestureRecognizerStateEnded) {
       alertView = [[UIAlertView alloc] initWithTitle:@"Server" message:@"" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Okay", nil];
    alertView.alertViewStyle = UIAlertViewStylePlainTextInput;
    myTextField = [alertView textFieldAtIndex:0];
    myTextField.text=mainString;
    [alertView show];
    [alertView release];

     }
    else if (sender.state == UIGestureRecognizerStateBegan){
       NSLog(@"UIGestureRecognizerStateBegan.");
   //Do Whatever You want on Began of Gesture
     }
  }

Answer 2

根据您的观察更改您longPressGestureRecognizer.minimumPressDuration的（时间间隔以秒为单位。默认持续时间为 0.5 秒。）或使用一些标志来检查是否已显示警报。