用Easing函数实现碰撞效果

工程中需要的源码请从这里下载：

源码：

////  ViewController.m//  EasingView////  Created by YouXianMing on 15/1/17.//  Copyright (c) 2015年 YouXianMing. All rights reserved.//#import "ViewController.h"#import "YXEasing.h"@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    // 显示的view    UIView *showView            = [[UIView alloc] initWithFrame:CGRectMake(100, -100, 100, 100)];    showView.backgroundColor    = [UIColor clearColor];    showView.layer.borderColor  = [UIColor redColor].CGColor;    showView.layer.borderWidth  = 4.f;    showView.layer.cornerRadius = 50.f;    [self.view addSubview:showView];        // 关键帧动画    CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:@"position"];        // 设置值    [animation setValues:[YXEasing calculateFrameFromPoint:showView.center                                                   toPoint:CGPointMake(showView.center.x, showView.center.y + 565)                                                      func:BounceEaseOut                                                frameCount:100]];        // 设置持续时间    animation.duration  = 1.f;        // 执行动画效果    showView.center = CGPointMake(showView.center.x, showView.center.y + 565);    [showView.layer addAnimation:animation forKey:nil];}@end