用POP动画引擎实现弹簧动画(POPSpringAnimation)

效果图:

#import "ViewController.h"
#import <POP.h>@interface ViewController ()@property (nonatomic, weak) UIView *testView;@end@implementation ViewController- (void)viewDidLoad
{[super viewDidLoad];self.view.backgroundColor = [UIColor blackColor];// 初始化测试控件UIView *testView         = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 50, 50)];testView.center          = self.view.center;testView.backgroundColor = [UIColor redColor];self.testView            = testView;[self.view addSubview:testView];
}- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{// 初始化弹簧动画POPSpringAnimation *springAnimation = [POPSpringAnimation animationWithPropertyNamed:kPOPLayerBounds];springAnimation.springSpeed         = 0;                    // 设置动画速度(常用)springAnimation.springBounciness    = 20;                   // 设置弹性大小(常用)// springAnimation.dynamicsFriction    = 10;                // 设置阻止弹性的阻力(选用)// springAnimation.dynamicsTension     = 100;               // 设置弹性的张力(可以理解为每次变大的程度, 选用)if (self.testView.frame.size.width == 100) {springAnimation.toValue = [NSValue valueWithCGRect:CGRectMake(0, 0, 50, 50)];} else {springAnimation.toValue = [NSValue valueWithCGRect:CGRectMake(0, 0, 100, 100)];}// 添加动画
    [self.testView.layer pop_addAnimation:springAnimation forKey:nil];
}@end

github:https://github.com/RinpeChen/POPSpringAnimationDemo