关键帧动画

/*
CAKeyframeAnimation 也属于 CAPropertyAnimation 
 关键帧动画  可以让我们精准是控制动画效果 它的原理是把动画序列里面比较关键的帧提取出来 设置他的动画效果
 
 path属性 执行动画轨迹的路径
 values 执行动画轨迹是数组
 
*/


#import "ViewController.h"

@interface ViewController ()
{
//    UIImage *image;
    CALayer *heartLayer;
//    CALayer *myLayer;
}
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    [self addHeart];
}

- (void)addHeart{
    
    UIImage *image = [UIImage imageNamed:@"桃心"];
    
    heartLayer = [[CALayer alloc]init];
    heartLayer.position = CGPointMake(self.view.center.x, 200);
    heartLayer.bounds = CGRectMake(0, 0, image.size.width/5, image.size.height/5);
    heartLayer.contents = (id)image.CGImage;
    
    [self.view.layer addSublayer:heartLayer];
}

- (void)addAnimation{
//    CAKeyframeAnimation 关键帧动画的类
    CAKeyframeAnimation *drow = [CAKeyframeAnimation animationWithKeyPath:@"position"];
    drow.duration = 0.001;
    drow.repeatCount = HUGE;
    drow.values = @[[self getPointWithX:0 andY:0],[self getPointWithX:50 andY:-50],[self getPointWithX:100 andY:-65],[self getPointWithX:120 andY:-50],[self getPointWithX:160 andY:0],[self getPointWithX:120 andY:100],[self getPointWithX:50 andY:150],[self getPointWithX:0 andY:200],[self getPointWithX:-50 andY:150],[self getPointWithX:-120 andY:100],[self getPointWithX:-160 andY:0],[self getPointWithX:-120 andY:-50],[self getPointWithX:-100 andY:-65],[self getPointWithX:-50 andY:-50],[self getPointWithX:0 andY:0]];
    
    [heartLayer addAnimation:drow forKey:@"move"];
    
}
#pragma mark-----把CGPoint 转换成NSValue--------
- (NSValue *)getPointWithX:(CGFloat)x andY:(CGFloat)y{
    
    return [NSValue valueWithCGPoint:CGPointMake(x+heartLayer.position.x, y+heartLayer.position.y)];
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    [self addAnimation];
}