iOS中实现弹簧动画

我们都知道iOS9 CASpringAnimation 弹簧动画，操作简单，容易实现，目前使用也比较广泛，下面我给大家介绍一种pop的弹簧效果，跟CASpringAnimation 弹簧动画 很相似
CocaPods加载 pod 'pop', '~> 1.0.9'

首先我们先看下动画的效果

2.gif

具体实现如下

#import "CSPlusVC.h"
#import "CSVerticalButton.h" //自定义封装的button
#import <POP.h>

@implementation CSPlusVC

- (void)viewDidLoad {
    [super viewDidLoad];
  
    [self addVerticalButtons];
  
}
- (void)addVerticalButtons{
 //点击之前 关闭交互
    self.view.userInteractionEnabled = NO;
//创建两个数组 分别存button上image的名字和title的名字
    NSArray *imagesArray = @[@"renwu",@"shuju",@"shudu",@"xianhua",@"yanlun",@"quantou"];
    NSArray *titleArray = @[@"人物",@"数据",@"数读",@"闲话",@"言论",@"拳头"];
   // kWidth为整屏宽，kHeight为整屏高
    CGFloat buttonW = kWidth*0.2;
    CGFloat buttonH = buttonW + 0.04*kHeight;
    CGFloat buttonStartY = (kHeight - 2*buttonW)*0.5;//buttonY的开始位置
    CGFloat buttonStartX = 20;
    int maxCols = 3;//每行最多三个
    
    CGFloat xMargin = (kWidth - 2*buttonStartX - maxCols *buttonW)/(maxCols-1); 
    
    for (int i=0;i<6;i++) {
  //添加6个button
        CSVerticalButton *button = [[CSVerticalButton alloc] init];
//设置button的相关属性
        button.titleLabel.font = [UIFont systemFontOfSize:15];
        [button setTitle:titleArray[i] forState:(UIControlStateNormal)];
        [button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
        [button setImage:[UIImage imageNamed:imagesArray[i]] forState:(UIControlStateNormal)];
        button.tag = i; //原始方法 给button一个tag值 用与后面点击方法
        [button addTarget:self action:@selector(clickButtonAciton:) forControlEvents:(UIControlEventTouchUpInside)];
        
        int row = i/maxCols; //行
        int col = i%maxCols;  //列
        CGFloat buttonX = buttonStartX+col*(buttonW+xMargin);
        CGFloat buttonEndY = buttonStartY +row*(buttonH+10);
        CGFloat buttonBeginY = buttonEndY -kHeight;
        [self.view addSubview:button];
        
//创建POPSpringAnimation动画 对象  动画结束位置就是button最终frame的位置 所以不需要一开始设置button在window中的位置 这也是跟CASpringAnimation的区别
        POPSpringAnimation *anim = [POPSpringAnimation animationWithPropertyNamed:kPOPViewFrame]; //改变frame
        anim.fromValue = [NSValue valueWithCGRect:CGRectMake(buttonX, buttonBeginY, buttonW, buttonH)];//动画开始位置
        anim.toValue = [NSValue valueWithCGRect:CGRectMake(buttonX, buttonEndY, buttonW, buttonH)];//动画结束位置
        anim.springBounciness = 15;//弹簧反弹弹度[4,20]
        anim.springSpeed  = 15;//弹簧速度[4,20]
        anim.beginTime = CACurrentMediaTime()+0.1*i;//动画开始时间
        //动画结束后 打开用户交互界面
        [anim setCompletionBlock:^(POPAnimation *anim, BOOL finished) {
            self.view.userInteractionEnabled = YES;
        }];
        [button pop_addAnimation:anim forKey:nil];
        
    }

    // 添加标语
    UIImageView *sloganView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"app_slogan"]];
    [self.view addSubview:sloganView];
    
    // 标语动画 
    POPSpringAnimation *anim = [POPSpringAnimation animationWithPropertyNamed:kPOPViewCenter]; //改变center位置
    CGFloat centerX = kWidth * 0.5;
    CGFloat centerEndY = kHeight * 0.2;
    CGFloat centerBeginY = centerEndY - kHeight;
    anim.fromValue = [NSValue valueWithCGPoint:CGPointMake(centerX, centerBeginY)];
    anim.toValue = [NSValue valueWithCGPoint:CGPointMake(centerX, centerEndY)];
    
    anim.springBounciness = 15;
    anim.springSpeed = 15;
    anim.beginTime = CACurrentMediaTime() + imagesArray.count * 0.1;
    [anim setCompletionBlock:^(POPAnimation *anim, BOOL finished) {
        // 标语动画执行完毕, 恢复点击事件
        self.view.userInteractionEnabled = YES;
    }];
    [sloganView pop_addAnimation:anim forKey:nil];
}
//取消按钮的方法
- (IBAction)cancelAction:(id)sender {
    
    [self cancelWithCompletionBlock:nil];
    
}

//取消的block方法
- (void)cancelWithCompletionBlock:(void(^)())completionBlock
{
 //关闭交互
    self.view.userInteractionEnabled = NO;
    int index = 0;
//遍历父视图   用于设置页面消失时的动画
    for (UIButton *button in self.view.subviews) {
        if ([button isKindOfClass:[CSVerticalButton class]]) {
  //给button设置下坠动画 用最普通的POPBasicAnimation就可以
            POPBasicAnimation *anim = [POPBasicAnimation animationWithPropertyNamed:kPOPViewCenter];
            CGFloat centerY = button.center.y + kHeight;
            anim.toValue = [NSValue valueWithCGPoint:CGPointMake(button.center.x, centerY)];
            anim.beginTime = CACurrentMediaTime()+ index*0.1;
            [button pop_addAnimation:anim forKey:nil];
            index++;
            if (index==5) { //在最后一个动画执行完毕后 ，页面退出 ，然后调用block ，block里执行要点击的事件
                [anim setCompletionBlock:^(POPAnimation *anim, BOOL finished) {
                    [self dismissViewControllerAnimated:NO completion:nil];
                    if (completionBlock) {
                        completionBlock();
                    }
                }];
            }
        }
    }

}

相信我写的已经很详细了，如有问提，请留言