Put a Button CGRECT Help

I have this code below, but the button only appears behind the image and just in the first image, how I can put the button over the all images?
[HTML]- (void)loadView
{
// Step 1: make the outer paging scroll view

CGRect frame = CGRectMake(10, 70, 300, 50);
UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
button.frame = frame;
[button setTitle:@"Click Me, Please!" forState:UIControlStateNormal];
button.backgroundColor = [UIColor clearColor];
button.tag = 2000;
[button addTarget:self
action:@selector(buttonClicked:)
forControlEvents:UIControlEventTouchUpInside];

CGRect pagingScrollViewFrame = [self frameForPagingScrollView];
pagingScrollView = [[UIScrollView alloc] initWithFrame:pagingScrollViewFrame];
pagingScrollView.pagingEnabled = YES;
pagingScrollView.backgroundColor = [UIColor blackColor];
pagingScrollView.showsVerticalScrollIndicator = NO;
pagingScrollView.showsHorizontalScrollIndicator = NO;
pagingScrollView.contentSize = CGSizeMake(pagingScrollViewFrame.size.width * [self pdfPageCount],

pagingScrollViewFrame.size.height);

[pagingScrollView addSubview:button];
pagingScrollView.delegate = self;
self.view = pagingScrollView;

// Step 2: prepare to tile content
recycledPages = [[NSMutableSet alloc] init];
visiblePages = [[NSMutableSet alloc] init];
[self tilePages];
}[/HTML]