appearing white shade while the view transitions? iwant to remove it

Question

i used the following code for swap between views..bute there appears a white shade ..how can i remove the white shade? help me

    CATransition *animation = [CATransition animation];

    [animation setDelegate:self];

 [animation setDuration:1.8];
 //[animation setTimingFunction:UIViewAnimationCurveEaseInOut];
 [animation setType: kCATransitionReveal];
 [animation setSubtype: kCATransitionFromRight];
 fromView.backgroundColor=[UIColor blackColor];

 [[toView layer] addAnimation:animation forKey:@"transitionViewAnimation"]; 
        [fromView addSubview:toView];