在景观模式下寻呼视图控制器

Question

我有这个代码，Apple的PageScrollView示例的修改版本。这里的差异在于使用ViewControllers而不是UIView。

MyClass.h

@interface MyClass : UIViewController { 
UIScrollView *scrollView; 
UIPageControl *pageControl; 
NSMutableArray *viewControllers; 
BOOL pageControlUsed; 
} 
@property (nonatomic, retain) IBOutlet UIScrollView *scrollView; 
@property (nonatomic, retain) IBOutlet UIPageControl *pageControl; 
@property (nonatomic, retain) NSMutableArray *viewControllers; 
- (IBAction)changePage:(id)sender; 
@end 

MyClass.m

#import "MyClass.h" 
#import "MyViewController.h" 
#import "MyViewControllerZero.h" 
#import "MyViewControllerOne.h" 
#import "MyViewControllerTwo.h" 

static NSUInteger kNumberOfPages = 3; 

@interface MyClass (PrivateMethods) 
- (void)loadScrollViewWithPage:(int)page; 
- (void)scrollViewDidScroll:(UIScrollView *)sender; 
@end 


@implementation MyClass 
@synthesize scrollView, pageControl, viewControllers; 

/* 
// The designated initializer. Override if you create the controller programmatically and want to perform customization that is not appropriate for viewDidLoad. 
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { 
    if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) { 
     // Custom initialization 
    } 
    return self; 
} 
*/ 


// Implement viewDidLoad to do additional setup after loading the view, typically from a nib. 
- (void)viewDidLoad { 
    NSMutableArray *controllers = [[NSMutableArray alloc] init]; 
    for (unsigned i = 0; i < kNumberOfPages; i++) { 
     [controllers addObject:[NSNull null]]; 
    } 
    self.viewControllers = controllers; 
    [controllers release]; 

    // a page is the width of the scroll view 
    scrollView.pagingEnabled = YES; 
    scrollView.contentSize = CGSizeMake(scrollView.frame.size.width * kNumberOfPages, scrollView.frame.size.height); 
    scrollView.showsHorizontalScrollIndicator = NO; 
    scrollView.showsVerticalScrollIndicator = NO; 
    scrollView.scrollsToTop = NO; 
    scrollView.delegate = self; 

    pageControl.numberOfPages = kNumberOfPages; 
    pageControl.currentPage = 0; 

    // pages are created on demand 
    // load the visible page 
    // load the page on either side to avoid flashes when the user starts scrolling 
    [self loadScrollViewWithPage:0]; 
    [self loadScrollViewWithPage:1]; 

} 

- (void)loadScrollViewWithPage:(int)page { 
    // if (page < 0) return; 
    // if (page >= kNumberOfPages) return; 
    if(page==0) 
    { 
     MyViewControllerZero *controller = [viewControllers objectAtIndex:page]; 
     if ((NSNull *)controller == [NSNull null]) 
     { controller = [[MyViewControllerZero alloc] init]; 
      [viewControllers replaceObjectAtIndex:page withObject:controller]; 
      if (nil == controller.view.superview) { 
       CGRect frame = scrollView.frame; 
       frame.origin.x = frame.size.width * page; 
       frame.origin.y = 0; 
       controller.view.frame = frame; 
       [scrollView addSubview:controller.view]; 
      } 


     } 
    } 

    if(page==1) 
    { 
     MyViewControllerOne *controller = [viewControllers objectAtIndex:page]; 
     if ((NSNull *)controller == [NSNull null]) 
     { controller = [[MyViewControllerOne alloc] init]; 
      [viewControllers replaceObjectAtIndex:page withObject:controller]; 
      if (nil == controller.view.superview) { 
       CGRect frame = scrollView.frame; 
       frame.origin.x = frame.size.width * page; 
       frame.origin.y = 0; 
       controller.view.frame = frame; 
       [scrollView addSubview:controller.view]; 
      } 


     } 
    } 

    if(page==2) 
    { 
     MyViewControllerTwo *controller = [viewControllers objectAtIndex:page]; 
     if ((NSNull *)controller == [NSNull null]) 
     { controller = [[MyViewControllerTwo alloc] init]; 
      [viewControllers replaceObjectAtIndex:page withObject:controller]; 
      if (nil == controller.view.superview) { 
       CGRect frame = scrollView.frame; 
       frame.origin.x = frame.size.width * page; 
       frame.origin.y = 0; 
       controller.view.frame = frame; 
       [scrollView addSubview:controller.view]; 
      } 


     } 
    } 
} 

- (void)scrollViewDidScroll:(UIScrollView *)sender { 
    if (pageControlUsed) { 
     return; 
    } 
    CGFloat pageWidth = scrollView.frame.size.width; 
    int page = floor((scrollView.contentOffset.x - 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 
} 


- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { 
    // Overriden to allow any orientation. 
    return YES; 
} 

- (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; 
} 
- (IBAction)changePage:(id)sender { 
    int page = pageControl.currentPage; 

    // 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]; 

    // update the scroll view to the appropriate page 
    CGRect frame = scrollView.frame; 
    frame.origin.x = frame.size.width * page; 
    frame.origin.y = 0; 
    [scrollView scrollRectToVisible:frame animated:YES]; 

    // Set the boolean used when scrolls originate from the UIPageControl. See scrollViewDidScroll: above. 
    pageControlUsed = YES; 
} 

- (void)didReceiveMemoryWarning { 
    // Releases the view if it doesn't have a superview. 
    [super didReceiveMemoryWarning]; 

    // Release any cached data, images, etc that aren't in use. 
} 


- (void)viewDidUnload { 
    [super viewDidUnload]; 
    // Release any retained subviews of the main view. 
    // e.g. self.myOutlet = nil; 
} 


- (void)dealloc { 
    [viewControllers release]; 
    [scrollView release]; 
    [pageControl release]; 

    [super dealloc]; 
} 


@end 

上面的代码中potrait模式下工作绝对没问题。但是，当我改变方向，整个页面被搞砸了..：（（

请帮我解决这个问题..

Answer 1

苹果没有设计的UIViewController在任何点视图层次合作。你添加到你的UIScrollView的视图是由视图控制器管理的，但我认为你会发现这些视图的视图控制器没有收到旋转事件

你可以尝试手动转发所有事件从滚动视图的控制器到子视图控制器，但我认为你会发现这是乏味和容易出错的，我建议你改为使用单个视图控制器来滚动视图，孩子的意见。