iphone - 你如何 CAKeyframeAnimation 缩放？

Question

我想创建一个有几个关键帧的动画。我希望我的图层（在这种情况下是一个按钮）放大到 1.5，然后缩小到 0.5，然后放大到 1.2，然后缩小到 0.8，然后缩小到 1.0。

我还想对每个关键帧进行 EaseIn 和 EaseOut。

可以想象，这将在现场产生弹性/弹跳效果。

在我的应用程序的其他部分，我一直在使用这样的 CAKeyframeAnimation（见下面的代码）。这将创建一个类似的弹性动画，但针对 x 和 y 位置。

我可以调整下面的代码来影响比例而不是位置吗？

先感谢您！

- (CAAnimation*)monInAnimation {
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path,NULL,113,320);
CGPathAddLineToPoint(path, NULL, 113.5, 283);
CGPathAddLineToPoint(path, NULL, 113.5, 179);
CGPathAddLineToPoint(path, NULL, 113.5, 207);  
CGPathAddLineToPoint(path, NULL, 113.5, 187);
CGPathAddLineToPoint(path, NULL, 113.5, 199);
CGPathAddLineToPoint(path, NULL, 113.5, 193);
CGPathAddLineToPoint(path, NULL, 113.5, 195);
CGPathAddLineToPoint(path, NULL, 113.5, 194);

CAKeyframeAnimation *
animation = [CAKeyframeAnimation 
             animationWithKeyPath:@"position"];

[animation setPath:path];
[animation setDuration:1.5];
[animation setCalculationMode:kCAAnimationLinear];
NSArray *arr = [NSArray arrayWithObjects:[NSNumber numberWithFloat:0.0], 
 [NSNumber numberWithFloat:0.12], 
 [NSNumber numberWithFloat:0.24], 
 [NSNumber numberWithFloat:0.36], 
 [NSNumber numberWithFloat:0.48],
 [NSNumber numberWithFloat:0.60],
 [NSNumber numberWithFloat:0.72],
 [NSNumber numberWithFloat:0.84],
 [NSNumber numberWithFloat:1.0],nil];

 [animation setKeyTimes:arr];
 [animation setTimingFunctions:[NSArray arrayWithObjects:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                                [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut], nil]];
 //[animation setAutoreverses:YES];
CFRelease(path);
return animation;

}

- (void)monBtnIn {

[monButton.layer setPosition:CGPointMake(113.5,194)];
[monButton.layer addAnimation:[self monInAnimation] 
                    forKey:@"position"];

}

Answer 1

为您提供两种替代解决方案：

首先，您还可以为变换属性设置动画。

使用 Brad 的代码，但使用 @"transform" 作为键路径。主要优点是您不必计算实际帧，而是提供一个简单的缩放因子：

目标-C：

CAKeyframeAnimation *boundsOvershootAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform"];

CATransform3D startingScale = CATransform3DScale (layer.transform, 0, 0, 0);
CATransform3D overshootScale = CATransform3DScale (layer.transform, 1.2, 1.2, 1.0);
CATransform3D undershootScale = CATransform3DScale (layer.transform, 0.9, 0.9, 1.0);
CATransform3D endingScale = layer.transform; 

NSArray *boundsValues = [NSArray arrayWithObjects:[NSValue valueWithCATransform3D:startingScale],
                                                  [NSValue valueWithCATransform3D:overshootScale],
                                                  [NSValue valueWithCATransform3D:undershootScale],
                                                  [NSValue valueWithCATransform3D:endingScale], nil];
[boundsOvershootAnimation setValues:boundsValues];

NSArray *times = [NSArray arrayWithObjects:[NSNumber numberWithFloat:0.0f],
                  [NSNumber numberWithFloat:0.5f],
                  [NSNumber numberWithFloat:0.9f],
                  [NSNumber numberWithFloat:1.0f], nil];    
[boundsOvershootAnimation setKeyTimes:times];


NSArray *timingFunctions = [NSArray arrayWithObjects:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut], 
                            [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                            [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                            nil];
[boundsOvershootAnimation setTimingFunctions:timingFunctions];
boundsOvershootAnimation.fillMode = kCAFillModeForwards;
boundsOvershootAnimation.removedOnCompletion = NO;

斯威夫特 4：

let boundsOvershootAnimation = CAKeyframeAnimation(keyPath: "transform")

let startingScale = CATransform3DScale(layer.transform, 0, 0, 0)
let overshootScale = CATransform3DScale(layer.transform, 1.2, 1.2, 1.0)
let undershootScale = CATransform3DScale(layer.transform, 0.9, 0.9, 1.0)
let endingScale = layer.transform

boundsOvershootAnimation.values = [startingScale, overshootScale, undershootScale, endingScale]

boundsOvershootAnimation.keyTimes = [0.0, 0.5, 0.9, 1.0].map { NSNumber(value: $0) }

boundsOvershootAnimation.timingFunctions = [
    CAMediaTimingFunction(name:kCAMediaTimingFunctionEaseOut),
    CAMediaTimingFunction(name:kCAMediaTimingFunctionEaseInEaseOut),
    CAMediaTimingFunction(name:kCAMediaTimingFunctionEaseInEaseOut)
]

boundsOvershootAnimation.fillMode = kCAFillModeForwards
boundsOvershootAnimation.isRemovedOnCompletion = false

其次，可能更容易的是使用 FTUtils，一个用于核心动画的开源包装器。它包括一个股票“弹性”动画。

您可以在以下网址获得它：http: //github.com/neror/ftutils

Answer 2

transform.scale， 任何人？

let anim = CAKeyframeAnimation(keyPath: "transform.scale")
anim.values = [0, 1, 0, 1, 0, 1, 0]
anim.duration = 4.0

smallView.layer.addAnimation(anim, forKey: "what")

---

完全不相关，如果要在 values 数组中使用浮点数，则必须将它们添加为NSNumbers，否则它们最终会变成 0！

anim.values = [0.0, 1.2, 0.9, 1.0].map { NSNumber(double: $0) }

Answer 3

与其设置 CAKeyframeAnimation 的路径，不如自己设置关键帧。我之前通过动画图层边界的大小创建了一个“弹出”效果：

CAKeyframeAnimation *boundsOvershootAnimation = [CAKeyframeAnimation animationWithKeyPath:@"bounds.size"];
CGSize startingSize = CGSizeZero;
CGSize overshootSize = CGSizeMake(targetSize.width * (1.0f + POPINOVERSHOOTPERCENTAGE), targetSize.height * (1.0f + POPINOVERSHOOTPERCENTAGE));
CGSize undershootSize = CGSizeMake(targetSize.width * (1.0f - POPINOVERSHOOTPERCENTAGE), targetSize.height * (1.0f - POPINOVERSHOOTPERCENTAGE));
NSArray *boundsValues = [NSArray arrayWithObjects:[NSValue valueWithCGSize:startingSize],
                         [NSValue valueWithCGSize:overshootSize],
                         [NSValue valueWithCGSize:undershootSize],
                         [NSValue valueWithCGSize:targetSize], nil];
[boundsOvershootAnimation setValues:boundsValues];

NSArray *times = [NSArray arrayWithObjects:[NSNumber numberWithFloat:0.0f],
                  [NSNumber numberWithFloat:0.5f],
                  [NSNumber numberWithFloat:0.9f],
                  [NSNumber numberWithFloat:1.0f], nil];    
[boundsOvershootAnimation setKeyTimes:times];


NSArray *timingFunctions = [NSArray arrayWithObjects:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut], 
                            [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                            [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut],
                            nil];
[boundsOvershootAnimation setTimingFunctions:timingFunctions];
boundsOvershootAnimation.fillMode = kCAFillModeForwards;
boundsOvershootAnimation.removedOnCompletion = NO;

其中 POPINOVERSHOOTPERCENTAGE 是我想要超出图层目标大小的分数。

Answer 4

我不知道您是否可以使用 CAKeyframeAnimation 为 UIView 的比例设置动画，但您可以使用 CABasicAnimation 并设置 fromValue 和 toValue 属性，并使用它来为 transform 属性设置动画：

- (CAAnimation*)monInAnimation 
{
    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"transform"];
    animation.fromValue = [NSValue valueWithCATransform3D:CATransform3DMakeScale(1.0, 1.0, 1.0)];
    animation.toValue = [NSValue valueWithCATransform3D:CATransform3DMakeScale(3.0, 3.0, 3.0)];
    [animation setDuration:1.5];
    [animation setAutoreverses:YES];
    return animation;
}

- (IBAction)monBtnIn 
{
    [monButton.layer addAnimation:[self monInAnimation] forKey:@"transform"];
}