CATransition Animation

    

    CATransition *tr=[CATransition  animation];

    tr.duration=1.0;

    tr.timingFunction=[CAMediaTimingFunction        functionWithName:kCAMediaTimingFunctionLinear];

    tr.type=kCATransitionPush;

    tr.subtype=kCATransitionFromBottom;

    tr.delegate=self;

    [self.view.layer addAnimation:tr forKey:nil];