zoom and pinch for scrollview

- (void)updateCachedPages
{
    int active = myVisiblePageNo;
	NSString *currentVisibleView=nil;
	for(int i=0; i<[myViewControllerArray count];i++)
	{

		if ( abs(active - (i)) <= 2 )
		{
			if(currentVisibleView==nil)
			{
				currentVisibleView=[NSString stringWithFormat:@"%d",i];
			}
			else
			{
				currentVisibleView=[currentVisibleView stringByAppendingString:[NSString stringWithFormat:@",%d",i]];
			}
			UIImageView *vController = [myViewControllerArray objectAtIndex:i];

            if ((NSNull *)vController == [NSNull null])
			{
				vController = [[UIImageView alloc] init];
                //vController.contentMode = UIViewContentModeCenter;

                for(int i=0 ;i<[ImageArray count];i++)
                {
                    NSString *strng=[ImageArray objectAtIndex:i];

                    vController.image= [self imageFromURLString:strng];
                    vController.tag = i;
                }

				[myViewControllerArray replaceObjectAtIndex:i withObject:vController];
				//myMaxTag=myMaxTag +1;
				[vController release];
			}

			if (nil == vController.superview)
			{
				vController.frame = CGRectMake(svObject.frame.size.width *i, svObject.frame.origin.y, self.svObject.frame.size.width, self.svObject.frame.size.height-93);
                [svObject addSubview:vController];
			}

				[svObject setContentSize:CGSizeMake((numberOfViewController * self.svObject.frame.size.width),vController.image.size.height)];

		}
		else
		{
			[myViewControllerArray replaceObjectAtIndex:i withObject:[NSNull null]];
        }

	}

	NSArray *mytempArray = [currentVisibleView componentsSeparatedByString:@","];
	UIView *view = nil;
	NSArray *subviews = [svObject subviews];
	for (view in subviews)
	{
		int myCount=0;
		BOOL isTagFound=FALSE;
		while(myCount<[mytempArray count])
		{
			int myTagNumber=[[mytempArray objectAtIndex:myCount] intValue];
			if(view.tag==myTagNumber)
			{
				isTagFound=TRUE;
				break;
			}
			myCount=myCount+1;
		}
		if(!isTagFound)
			[view removeFromSuperview];

	}
}
-(UIView *) viewForZoomingInScrollView:(UIScrollView *)scrollView
{
    for(UIView *subview in [scrollView subviews])
    {
        if([subview isKindOfClass:[UIImageView class]])
        {
            NSLog(@"%d",[subview tag]);
            return subview;
        }
    }
}