iOS缩放动画

    CABasicAnimation *pulseAnimation = [CABasicAnimation animationWithKeyPath:@"transform.scale"];

    pulseAnimation.duration = .5;

    pulseAnimation.fromValue=[NSNumber numberWithFloat:0];

    //pulseAnimation.toValue = [NSNumber numberWithFloat:1];

    pulseAnimation.byValue = [NSNumber numberWithFloat:1];

    pulseAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];

    pulseAnimation.autoreverses = NO;

    pulseAnimation.repeatCount = 1;

    

    [backPackInfoView.layer addAnimation:pulseAnimation forKey:nil];