iOS仿小红书呼吸灯动画(核心动画和定时器)两种方式实现

-(void)begigFlashAnimation {  // 缩放 + 透明度动画  self.flashView.transform = CGAffineTransformMakeScale(0.1, 0.1);  [UIView animateWithDuration:3 animations:^{    self.flashView.transform = CGAffineTransformMakeScale(1,1);    self.flashView.alpha = 1.0;    [UIView beginAnimations:@"flash" context:nil];    [UIView setAnimationDuration:2];    [UIView setAnimationCurve:UIViewAnimationCurveLinear];    self.flashView.alpha = 0;    [UIView commitAnimations];  }];}

- (CAAnimationGroup *)groups {  if (!_groups) {    // 缩放动画    CABasicAnimation * scaleAnim = [CABasicAnimation animation];    scaleAnim.keyPath = @"transform.scale";    scaleAnim.fromValue = @0.1;    scaleAnim.toValue = @1;    scaleAnim.duration = 2;    // 透明度动画    CABasicAnimation *opacityAnim=[CABasicAnimation animationWithKeyPath:@"opacity"];    opacityAnim.fromValue= @1;    opacityAnim.toValue= @0.1;    opacityAnim.duration= 2;    // 创建动画组    _groups =[CAAnimationGroup animation];    _groups.animations = @[scaleAnim,opacityAnim];    _groups.removedOnCompletion = NO;    _groups.fillMode = kCAFillModeForwards;    _groups.duration = 2;    _groups.repeatCount = FLT_MAX;  }  return _groups;}