UILabel UILongPressGestureRecognizer不工作？

Question

如何在uilabel上獲取UILongPressGestureRecognizer？當我實現下面的代碼時，它不會調用該函數。所以請告訴我我做了什麼錯誤？

UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc]  initWithTarget:self action:@selector(LabelLongPressed:)]; 
longPress.minimumPressDuration = 0.5; // Seconds 
longPress.numberOfTapsRequired = 0; 

[objlblDuplicate addGestureRecognizer:longPress]; 
[longPress release]; 

Answer 1

默認情況下，UILabel無法獲取觸摸事件。

objlblDuplicate.userInteractionEnabled = YES;