UIScrollView "back to original size"

I have a UIScrollView which has a UIView embedded in it. It scrolls up from bottom on a buttonClick, the button is located in another view. When it scrolls up it partly covers the calling view i.e view on which the button is 开发者_如何学编程located. Now, I have another button that is supposed to push this scroll view down. This button doesn't seem to be working. I have posted the entire code. Please Help!!

-(IBAction)unscrollClicked:(id)sender
{
 //[viewController.view removeFromSuperview]; 
 [UIView beginAnimations:@"back to original size" context:nil];

 scrollView.contentSize=viewController.view.bounds.size;


 //scrollView.contentSize=viewController.view.bounds.size;
 [UIView commitAnimations];

}

-(IBAction)scrollClicked:(id)sender

{

 //viewController.view.backgroundColor=[UIColor orangeColor];
 viewController.view.frame=CGRectMake(0, 410, 320, 460);

 //[self.view addSubview:viewController.view];

 UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0,40, 320, 400)];//(0,0,320,160)
 scrollView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;

 //[MyView setFrame:CGRectMake (0, 0, 320, 170)];
 viewController.view.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
 scrollView.contentSize = viewController.view.bounds.size;


 scrollView.bounces = YES;
 scrollView.bouncesZoom = YES;
 scrollView.scrollEnabled = YES;
 scrollView.minimumZoomScale = 0.5;
 scrollView.maximumZoomScale = 5.0;
 scrollView.delegate = self;

 [scrollView addSubview: viewController.view];


 [self.view addSubview:scrollView];
 [self moveScrollView:scrollView];
}

-(void) moveScrollView:(UIScrollView *)scrollView

{

 CGFloat scrollamount=400;



 [scrollView setContentOffset:CGPointMake(0,scrollamount) animated:YES];
}

Try using the zoomToRect method.

I think you should modify your move method. As it is, it shows content at a fixed origin ( height 400), but after one invokation it should not do anything, since contentOffset is already at 400. Try this:

-(void) moveScrollView:(UIScrollView *)scrollView upwards:(BOOL)up {
     CGFloat scrollamount=400;

if ( up)
    [scrollView setContentOffset:CGPointMake(0,scrollamount) animated:YES];
else
    [scrollView setContentOffset:CGPointMake(0,0) animated:YES];
}

And invoke like this:

[self moveScrollView:scrollView upwards:YES]; // or NO for moving down