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我在处理旋转时在iPhone上使用UIScrollView时遇到了问题。我使用Apple的PageControl示例作为模型，但是我自己在View中创建了scrollview。使用分页旋转UIScrollView的问题
1）滚动视图按预期工作在默认的纵向加载时，向左滚动向右水平
2）开箱，旋转CW和重新初始化时，大多把它在其一侧，现在旋转垂直向下，而不是期望的水平静止。看起来scrollview框架的宽度/高度不会改变，只是它自己的方向。
3）我试图添加一些方向检测逻辑，以正确的大小和页面滚动视图的方向，这种工作方式，但只有当我将CCW旋转到横向。如果我去CW，它会从右边开始滚动到左边，并且不起作用。
很明显，这是越来越hackish，所以有没有一种适当的方式来设置我的UIScrollview并重新使它旋转，所以它总是从左到右滚动？
- (void)loadView {
[self setupPage];
}
-(void) setupPage {
// lazy init view controllers
NSMutableArray *controllers = [[NSMutableArray alloc] init];
for (unsigned i = 0; i = kNumberOfPages) return;
// replace the placeholder if necessary
MyViewController *controller = [viewControllers objectAtIndex:page];
if ((NSNull *)controller == [NSNull null]) {
controller = [[MyViewController alloc] initWithPageNumber:page];
[viewControllers replaceObjectAtIndex:page withObject:controller];
[controller release];
}
// add the controller's view to the scroll view
if (nil == controller.view.superview) {
CGRect frame = scrollView.frame;
int x = 0;
int y = 0;
UIDeviceOrientation orientation = [[UIDevice currentDevice] orientation];
if(orientation == UIDeviceOrientationLandscapeLeft || orientation == UIDeviceOrientationLandscapeRight){
x = 0;
y = frame.size.height * page;
} else {
x = frame.size.width * page;
y = 0;
}
frame.origin.x = x;
frame.origin.y = y;
controller.view.frame = frame;
[scrollView addSubview:controller.view];
}
}
- (void)scrollViewDidScroll:(UIScrollView *)sender {
// We don't want a "feedback loop" between the UIPageControl and the scroll delegate in
// which a scroll event generated from the user hitting the page control triggers updates from
// the delegate method. We use a boolean to disable the delegate logic when the page control is used.
if (pageControlUsed) {
// do nothing - the scroll was initiated from the page control, not the user dragging
return;
}
// Switch the indicator when more than 50% of the previous/next page is visible
CGFloat pageWidth = scrollView.frame.size.width;
int offset = 0;
UIDeviceOrientation orientation = [[UIDevice currentDevice] orientation];
if(orientation == UIDeviceOrientationLandscapeLeft || orientation == UIDeviceOrientationLandscapeRight){
pageWidth = scrollView.frame.size.height;
offset = scrollView.contentOffset.y;
} else {
pageWidth = scrollView.frame.size.width;
offset = scrollView.contentOffset.x ;
}
//CGFloat pageWidth = scrollView.frame.size.width;
int page = floor((offset - pageWidth/2)/pageWidth) + 1;
pageControl.currentPage = page;
// load the visible page and the page on either side of it (to avoid flashes when the user starts scrolling)
[self loadScrollViewWithPage:page - 1];
[self loadScrollViewWithPage:page];
[self loadScrollViewWithPage:page + 1];
// A possible optimization would be to unload the views+controllers which are no longer visible
}
// At the begin of scroll dragging, reset the boolean used when scrolls originate from the UIPageControl
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView {
pageControlUsed = NO;
}
// At the end of scroll animation, reset the boolean used when scrolls originate from the UIPageControl
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
pageControlUsed = NO;
}
- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
[self setupPage];
}