实例讲解iOS应用UI开发之基础动画的创建

@interface YYViewController ()
@property(nonatomic,strong)CALayer *myLayer;
@end

@implementation YYViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    
    //创建layer
    CALayer *myLayer=[CALayer layer];
    //设置layer的属性
    myLayer.bounds=CGRectMake(0, 0, 50, 80);
    myLayer.backgroundColor=[UIColor yellowColor].CGColor;
    myLayer.position=CGPointMake(50, 50);
    myLayer.anchorPoint=CGPointMake(0, 0);
    myLayer.cornerRadius=20;
    //添加layer
    [self.view.layer addSublayer:myLayer];
    self.myLayer=myLayer;
}

//设置动画（基础动画）
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    //1.创建核心动画
    //    CABasicAnimation *anima=[CABasicAnimation animationWithKeyPath:<#(NSString *)#>]
    CABasicAnimation *anima=[CABasicAnimation animation];
    
    //1.1告诉系统要执行什么样的动画
    anima.keyPath=@"position";
    //设置通过动画，将layer从哪儿移动到哪儿
    anima.fromValue=[NSValue valueWithCGPoint:CGPointMake(0, 0)];
    anima.toValue=[NSValue valueWithCGPoint:CGPointMake(200, 300)];
    
    //1.2设置动画执行完毕之后不删除动画
    anima.removedOnCompletion=NO;
    //1.3设置保存动画的最新状态
    anima.fillMode=kCAFillModeForwards;
    anima.delegate=self;
    //打印
    NSString *str=NSStringFromCGPoint(self.myLayer.position);
    NSLog(@"执行前：%@",str);
    
    //2.添加核心动画到layer
    [self.myLayer addAnimation:anima forKey:nil];

}

-(void)animationDidStart:(CAAnimation *)anim
{
    NSLog(@"开始执行动画");
}

-(void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag
{
    //动画执行完毕，打印执行完毕后的position值