Question

我正在尝试创建一个应用程序，当UILongPressGestureRecognizer手势被触发时，UIButtons可以被拖放。实际上我的应用程序在任何iPad上运行良好。它仅在iPhone中产生问题，并且低于iOS 5.0，因此在使用iOS 5.0的iPhone中工作得很好。

UILongPressGestureRecognizer * gesture = [[UILongPressGestureRecognizer alloc] initWithTarget: self action: @selector(moveActionGestureRecognizerStateChanged:)];
gesture.minimumPressDuration = 0.5;
gesture.delegate = self;
[self.dragView addGestureRecognizer: gesture];
[gesture release]; 

- (void) moveActionGestureRecognizerStateChanged: (UILongPressGestureRecognizer *) recognizer
{
    switch ( recognizer.state )
    {
        default:
        case UIGestureRecognizerStateFailed:
        {
            dragView.alpha=1.0;
            [dragView release];
            dragView=nil;
            break;
        }
        case UIGestureRecognizerStatePossible:
        {
               dragView.alpha=0.8;
            dragView.frame=CGRectMake(dragView.frame.origin.x, dragView.frame.origin.y, dragView.frame.size.width, dragView.frame.size.height);
        }
        case UIGestureRecognizerStateCancelled:
        {
            dragView.alpha=1.0;
            [dragView release];
            dragView=nil;
            break;
        }            
        case UIGestureRecognizerStateEnded:
        {
            //Set dragView on target position

            break;
        }
        case UIGestureRecognizerStateBegan:
        {
            //NSLog(@"Began");
            dragView.alpha=0.8;        
            dragView.frame=CGRectMake(dragView.frame.origin.x, dragView.frame.origin.y, dragView.frame.size.width, dragView.frame.size.height);
            [self bringSubviewToFront:dragView];
            break;
        }           
        case UIGestureRecognizerStateChanged:
        {
            [self.view bringSubviewToFront:dragView];
            CGPoint offset = [recognizer locationInView: self.scrollView];
            dragView.frame=CGRectMake(offset.x, offset.y, dragView.frame.size.width, dragView.frame.size.height);
        }            
            break;
    }
}

我有2台设备iPhone 3G与iOS 4.2.1和iPhone 4与5.0。此功能在带有iOS 5.0的iPhone 4中运行良好，但在带有iOS 4.2.1的iPhone 3g中无法正常工作。有时它在iPhone 3g中工作，但有时它不会调用委托方法。

如果您有任何解决方案，请告诉我。

谢谢！

Answer 1

是否根本没有调用委托方法，或者没有选择案例？我不知道这是否真的解决了你的问题，但你应该修复你的switch（在默认情况下抢劫）：

switch ( recognizer.state )
{
    case someCase:
    {
        // ...
        break;
    }

    default:
        break;
}

UILongPressGestureRecognizer无法正常工作

1 个答案: