我想在 View 的两种状态之间设置动画。比方说，我有一个带有标签的 View ，当我更改标签的文本时，动画会呈现出翻页的变化。

现在你当然可以用 [UIView setAnimationTransition:forView:cache:]:

- (IBAction)nextPage {
    [UIView beginAnimation:nil context:nil];
    [UIView setAnimationDuration:1];
    [UIView setAnimationTransition:UIViewAnimationTransitionCurlUp forView:pageView cache:NO];
    label.text = @"page 2";
    [UIView commitAnimations];
}

- (IBAction)previousPage {
    [UIView beginAnimation:nil context:nil];
    [UIView setAnimationDuration:1];
    [UIView setAnimationTransition:UIViewAnimationTransitionCurlDown forView:pageView cache:NO];
    label.text = @"page 1";
    [UIView commitAnimations];
}

...但是您不能使用自己的自定义动画，您只能使用内置动画(它们很好，但不适合我的需要)。

所以另一种选择是将 CAAnimation 添加到 View 层:

- (IBAction)nextPage {
    CAAnimation *animation = [self animationWithDuration:1 forward:NO];
    [pageView.layer addAnimation:animation forKey:@"pageTransition"];
    label.text = @"page 2";
}

- (IBAction)previousPage {
    CAAnimation *animation = [self animationWithDuration:1 forward:YES];
    [pageView.layer addAnimation:animation forKey:@"pageTransition"];
    label.text = @"page 1";
}

然后您可以自由设置 Core Animation 允许您执行的任何动画。如果我定义一个 CATransition 动画，例如 kCATransitionReveal，这会很好地工作:“第 2 页”状态的 View 显示在“第 1 页”状态的 View 下方，如下所示它滑了出来。

- (CAAnimation *)animationWithDuration:(float)duration forward:(BOOL)forward {
    CATransition *animation = [CATransition animation]; 
    [animation setType:kCATransitionReveal];
    [animation setSubtype:forward?kCATransitionFromLeft:kCATransitionFromRight];
    [animation setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn]];

    animation.duration = duration; 
    return animation; 
}

但是当我将动画定义为例如 CABasicAnimation 时，只有一种 View 状态是可见的。

- (CAAnimation *)animationWithDuration:(float)duration forward:(BOOL)forward {
    CATransform3D transform = CATransform3DIdentity;
    transform.m34 = 1.0 / -1000;
    transform = CATransform3DRotate(transform, M_PI, 0.0f, 1.0f, 0.0f);
    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"transform"];
    if(forward) {
        animation.fromValue = [NSValue valueWithCATransform3D:transform];
    } else {
        animation.toValue = [NSValue valueWithCATransform3D:transform];
    }

    animation.duration = duration; 
    return animation; 
}

相反，我希望处于“第 1 页”状态的 View 在动画结束之前保持可见，而处于“第 2 页”状态的 View 进入框架，就像它在过渡动画中的行为一样。

当然，当我为最前面的 View 设置动画并在完成时将其从 super View 中删除时，我总是会复制 View 并让一个 View 显示为同级 View ......但必须有更直接的方法来实现这一点相当简单的动画效果，不会弄乱 View 。

可能是要告诉层，但我不知道是什么，这就是我需要你们帮助的地方，伙计们:)

谢谢!

最佳答案

我最近在 Controller 中的 subview 之间进行了自定义幻灯片转换。我的方法是获取 View 输出和 View 输入的位图，将它们添加到 View 并为该 View 设置动画。最后，您可以删除过渡 View 并显示 View 。这是过渡方法的片段:

-(void) transitionToView:(UIView *)viewIn lastView:(UIView *)viewOut slideRight:(BOOL)isRight { 
UIGraphicsBeginImageContext(viewOut.frame.size);

UIImageView *bitmapOut = [[UIImageView alloc] initWithFrame: viewOut.frame];

[viewOut.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewOutImage = UIGraphicsGetImageFromCurrentImageContext();   
UIGraphicsEndImageContext();
bitmapOut.image = viewOutImage;

UIImageView *bitmapIn = [[UIImageView alloc] initWithFrame: viewIn.frame ];
bitmapIn.frame = CGRectMake(isRight ? 320 : -320, bitmapIn.frame.origin.y, bitmapIn.frame.size.width, bitmapIn.frame.size.height);
UIGraphicsBeginImageContext(viewIn.frame.size);

[viewIn.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewInImage = UIGraphicsGetImageFromCurrentImageContext();   
UIGraphicsEndImageContext();

bitmapIn.image = viewInImage;

[self.view addSubview:transitionContainer];

[transitionContainer addSubview:bitmapIn];
[transitionContainer addSubview:bitmapOut];

[self removeAllViews];

[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.5f];
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:@selector(swapViewsAtEndOfTransition:)];
transitionContainer.frame = CGRectMake(isRight ? -320 : 320, 0, 640, 411);
[UIView commitAnimations];

[bitmapOut release]; bitmapOut = nil;
[bitmapIn release]; bitmapIn = nil;}

然后，在 swapViewsAtEndOfTransition 选择器中，您可以相应地更新 View 。

关于ios - 使用自定义动画在 View 的两种状态之间进行动画处理，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/3157837/