UILongPressGestureRecognizer 问题

Question

我有一个关于 UILongPressGestureRecognizer 的问题，我添加了如下代码所示的手势

**ViewDidLoad**
UILongPressGestureRecognizer *_longRecognizer = [[UILongPressGestureRecognizer alloc]      initWithTarget:self action:@selector(ICN_TRASH_Click:)]; 
NSArray *recognizerArray = [[NSArray alloc] initWithObjects:_longRecognizer, nil];

[[self.view viewWithTag:2001] setGestureRecognizers:recognizerArray];

 OnClick
 if ([sender isKindOfClass:[UILongPressGestureRecognizer class]])  
{

  UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Warning" message:@"Are you sure delete all message ?" delegate:self cancelButtonTitle:@"Yes" otherButtonTitles:@"No",nil];
  [alert show];
  [alert release];

}

所以我们长按按钮两次调用alertview， 有谁知道，为什么要面对这个问题。

Answer 1

所以你按下按钮（然后我猜是松开它），你会收到两次消息？

也许您应该检查 GestureRecognizer 的状态（例如是开始阶段还是结束阶段）GestureRecognizer state。