CAAnimationGroup顺序执行animation

    CABasicAnimation *animation31 =[CABasicAnimation

                                   animationWithKeyPath: @"position.x" ];

    [animation31 setToValue:[NSNumber numberWithFloat:470]]; 

    animation31.cumulative=YES;

    animation31.duration =.1;

    [animation31 setFillMode:kCAFillModeForwards];  

    animation31.timingFunction = [CAMediaTimingFunctionfunctionWithName:kCAMediaTimingFunctionEaseIn];

    [animation31 setRemovedOnCompletion:NO];  

    

   CAAnimationGroup *group = [CAAnimationGroupanimation];

    group.animations = [NSArrayarrayWithObjects:animation31, nil];

    group.duration =.1;

    group.timingFunction = [CAMediaTimingFunctionfunctionWithName:kCAMediaTimingFunctionEaseInEaseOut];

    group.autoreverses =YES;

    group.repeatCount =2;

    

    [garbagebutton.layeraddAnimation:group forKey:nil];