iOS学习——核心动画

3、 简单使用CoreAnimation的步骤

KeyPath常用的属性：

• kCAMediaTimingFunctionLinear，在整个动画时间内动画都是以一个相同的速度来改变，也就是匀速运动。一个线性的计时函数，同样也是CAAnimation的timingFunction属性为空时候的默认函数。线性步调对于那些立即加速并且保持匀速到达终点的场景会有意义（例如射出枪膛的子弹）。

/* CABasicAnimation应用
    心跳效果
    思路:就是让一张图片做一个放大缩放小的动画.
*/
    
//代码实现:
     
- (void) viewDidLoad {
    CABasicAnimation *anim =[CABasicAnimation  animation];
    //设置缩放属性
    anim.keyPath = @"transform.scale";
    //缩放到一半
    anim.toValue = @0.5;
    //设置动画执行的次数
    anim.repeatCount = MAXFLOAT;
    //设置动画执行的时长
    anim.duration = 0.25;
    //设置动画自动反转(怎么去, 怎么回)
    anim.autoreverses = YES;
    //添加动画
    [self.heartView.layer addAnimation:anim forKey:nil];
}

/* CAKeyframeAnimation的应用
    图片抖动
    思路：其实就是做一个左右旋转的动画.先让它往左边旋转-5,再往右边旋转5度,再从5度旋转到-5度. 就会有左右摇摆的效果了.
*/
        
//图标抖动代码实现
- (void)values{

    //创建一个帧动画
    CAKeyframeAnimation *anim = [CAKeyframeAnimation animation];    
    //设置属性
    anim.keyPath = @"transform.rotation";    
    //设置属性值.
    anim.values = @[@(angle2Rad(-5)),@(angle2Rad(5)),@(angle2Rad(-5))];
    //设置执行的次数
    anim.repeatCount = MAXFLOAT;
    
    anim.duration = 0.25;
    
    //添加动画
    [self.iconV.layer addAnimation:anim forKey:nil];

}

//我们还可以直接设置关键帧CAKeyframeAnimation动画的路径 path属性

-(void)touchesBegan:(nonnull NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{
    
    //创建一个帧动画
    CAKeyframeAnimation *anim = [CAKeyframeAnimation animation];
    
    //设置属性
    anim.keyPath = @"position";
    //直接设置动画的路径path是画弧
    UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(50, 50, 300, 400)];   
    anim.path = path.CGPath;

    //设置执行的次数
    anim.repeatCount = MAXFLOAT;
   //设置是否反转
    anim.autoreverses = YES;
    
    anim.duration = 1;
    
    //添加动画
    [self.iconV.layer addAnimation:anim forKey:nil];
}

-(void)touchesBegan:(nonnull NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{
    //UIView执行转场动画
    [UIView transitionWithView:self.imageV duration:1 options:UIViewAnimationOptionTransitionCrossDissolve animations:^{

        _i++;
        if (_i > 3) {
            _i = 1;
        }
        NSString *imageName = [NSString stringWithFormat:@"%d",_i];
        self.imageV.image = [UIImage imageNamed:imageName];

    } completion:nil];    
    
}

-(void)touchesBegan:(nonnull NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{

    //转场代码必须得要和转场动画在同一个方法当中.
    //创建动画
    CATransition *anim = [CATransition animation];
    //设置转场类型
    anim.type = @"cube";
    //设置转场的方向
    anim.subtype = kCATransitionFromTop;
    //设置动画的开始点.
    anim.startProgress = 0.2;
    //设置动画的结束点.
    anim.endProgress = 0.8;

    [self.imageV.layer addAnimation:anim forKey:nil];
    
    //转场代码必须得要和转场动画在同一个方法当中.
    _i++;
    if (_i > 3) {
        _i = 1;
    }
    NSString *imageName = [NSString stringWithFormat:@"%d",_i];
    self.imageV.image = [UIImage imageNamed:imageName]; 
}

- (void)springAni {
    CASpringAnimation * ani = [CASpringAnimation animationWithKeyPath:@"bounds"];
    ani.mass = 10.0; //质量，影响图层运动时的弹簧惯性，质量越大，弹簧拉伸和压缩的幅度越大
    ani.stiffness = 5000; //刚度系数(劲度系数/弹性系数)，刚度系数越大，形变产生的力就越大，运动越快
    ani.damping = 100.0;//阻尼系数，阻止弹簧伸缩的系数，阻尼系数越大，停止越快
    ani.initialVelocity = 5.f;//初始速率，动画视图的初始速度大小;速率为正数时，速度方向与运动方向一致，速率为负数时，速度方向与运动方向相反
    ani.duration = ani.settlingDuration;
    ani.toValue = [NSValue valueWithCGRect:self.centerShow.bounds];
    ani.removedOnCompletion = NO;
    ani.fillMode = kCAFillModeForwards;
    ani.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
    [self.cartCenter.layer addAnimation:ani forKey:@"boundsAni"];
}

-(void)touchesBegan:(nonnull NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{
  
    CAAnimationGroup *group = [CAAnimationGroup animation];
    
    //缩放
    CABasicAnimation *scaleAnim = [CABasicAnimation animation];
    //设置属性
    scaleAnim.keyPath = @"transform.scale";
    scaleAnim.toValue = @0.5;

    //平移
    CABasicAnimation *Anim = [CABasicAnimation animation];
    //设置属性
    Anim.keyPath = @"position.y";
    Anim.toValue = @(400);

    //将上面两个动画添加到动画组
    group.animations = @[scaleAnim,Anim];
    
    //设置动画的属性，一定要在动画组上设置
    group.removedOnCompletion = NO;
    group.fillMode  = kCAFillModeForwards;
    //添加动画
    [self.redView.layer addAnimation:group forKey:nil];
    
}