用手势滑动视图

我正在尝试开发一个应用程序给Iphone;但我是新的蜜蜂，所以我有很多问题。用手势滑动视图

我的应用程序有一个默认视图和主视图中名称为flashcard的另一个小视图。

我想增加这个视图在Iphone中像照片一样滑动（或滑动）的功能。例如，如果用户滑动视图直到内部视图的中心到达主视图的边界，则将有两种可能性，1 - 如果用户在到达内部视图之前完成滑动，则会返回原始位置。 012-2-如果用户不停止滑动，内部视图将从滑动方向在屏幕上熄灭，并从相反方向返回屏幕。

所以我宣布UIPanGestureRecognizer在viewDidLoad中像下面

UIPanGestureRecognizer *panFlashCard = [[UIPanGestureRecognizer alloc] 
             initWithTarget:self action:@selector(handlePanFlashCard:)]; 

[flashcard addGestureRecognizer:panFlashCard]; 
[panFlashCard release];

handPanFlashCard行动：

UIView *piece = [recognizer view]; 
    CGPoint center = piece.center; 
    CGFloat x = 160; // the original x axis of inner view 

    if ([recognizer state] == UIGestureRecognizerStateChanged) { 
     CGPoint translation = [recognizer translationInView:piece ]; 
     [UIView beginAnimations:nil context:NULL]; 
     [UIView setAnimationDuration:0.55]; 
     [piece setCenter:CGPointMake(piece.center.x + translation.x, center.y)]; 
     [UIView commitAnimations]; 
     CGFloat totalX; 
     totalX= x + translation.x; 
     if(translation.x <0) 
     {    
      if (totalX <= 0) 
      { 
       [self showNextCard]; 
      } 
      else 
      { 
       [UIView beginAnimations:nil context:NULL]; 
          [UIView setAnimationDuration:0.55]; 
          [piece setCenter:CGPointMake(self.view.center.x, center.y)]; 
          [UIView commitAnimations]; 
      } 
     } 
     else 
     { 
      if (totalX >= self.view.bounds.size.width) 
      { 
       [self showPreviousCard]; 
      } 
      else 
      { 
       [UIView beginAnimations:nil context:NULL]; 
       [UIView setAnimationDuration:0.55]; 
       [piece setCenter:CGPointMake(self.view.center.x, center.y)]; 
       [UIView commitAnimations]; 
      } 
     } 
    }

showNextCard行动：

[flashcard setCenter:CGPointMake(self.view.bounds.size.width + flashcard.bounds.size.width, flashcard.center.y)]; 

    [UIView beginAnimations:nil context:NULL]; 
    [UIView setAnimationDuration:0.55]; 
    [flashcard setCenter:CGPointMake(self.view.center.x, flashcard.center.y)]; 
    [UIView commitAnimations];

showPreviousCard行动：

[flashcard setCenter:CGPointMake(0 - flashcard.bounds.size.width, flashcard.center.y)]; 

    [UIView beginAnimations:nil context:NULL]; 
    [UIView setAnimationDuration:0.55]; 
    [flashcard setCenter:CGPointMake(self.view.center.x, flashcard.center.y)]; 
    [UIView commitAnimations];

当我运行这个应用程序，它建立并运行成功，但有动画错误，我认为一些框架错误。

请帮我改正这段代码，并在滑动时运行流畅的动画。

来源

2011-05-04 bahadir arslan