ios：<Error>：CGAffineTransformInvert：奇异matrix
任何此错误的原因“CGAffineTransformInvert”
我应该担心吗？
我有一个视图的.xib，和4个位于视图之外，但在同一个xib中的webViews。 然后在代码中，我将webViews作为子视图添加到视图内的滚动视图中。 会导致这个问题吗？
代码如下：
//Called first to initialize this class. Also, initializes the nib file and tab bar name. - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; if (self) { self.title = NSLocalizedString(@"More", @"More"); self.tabBarItem.image = [UIImage imageNamed:@"first"]; } return self; } //Initialize the more tab titles and views -(void)initViewsandTitles{ MoreTabPages = [NSArray arrayWithObjects:self.aboutWebView, self.newsUpdateWebView, self.feedbackWebView, self.creditsResourceWebView, nil]; titles = [[NSArray alloc] initWithObjects:@"About Locavore", @"News and Updates", @"Feedback", @"Credits and Resources", nil]; } //Initialize the URLs -(void)initURLs{ websites = [[NSArray alloc] initWithObjects:@"http://www.getlocavore.com/", @"http://twitter.com/enjoy_locavore", @"https://getsatisfaction.com/localdirt/products/localdirt_locavore", @"http://www.getlocavore.com/about", nil]; } //Called after the controller's view is loaded into memory. - (void)viewDidLoad { [super viewDidLoad]; //Call the super class init method [self setupSpinner]; //Start the spinner animatio [self initViewsandTitles]; //Initialize the views and titles [self initURLs]; //Initialize the URLs [self setScrollandPageViewProperties]; //Set the scroll and page view properties [self setUpPageViews]; //Create the web pages } //UIScrollViewDelegate Protocol Reference. Called whn the user scrolls the content within the reciever - (void)scrollViewDidScroll:(UIScrollView *)sender { if (!pageControlBeingUsed) { // Switch the indicator when more than 50% of the previous/next page is visible CGFloat pageWidth = self.MoreTabScrollView.frame.size.width; int page = floor((self.MoreTabScrollView.contentOffset.x - pageWidth / 2) / pageWidth) + 1; self.MoreTabPageControl.currentPage = page; self.MoreTabTitle.text = [titles objectAtIndex:page]; } } //UIScrollViewDelegate Protocol Reference. Called when the scroll view is about to start scolling content - (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView { pageControlBeingUsed = NO; } //UIScrollViewDelegate Protocol Reference. Called when the scroll view has ended decelerating the scrolling movement - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView { NSLog(@"DID END SCROLLING"); pageControlBeingUsed = NO; } //Called when the page control value changes - (IBAction)MoreTabChangePage { // Update the scroll view to the appropriate page CGRect frame; frame.origin.x = self.MoreTabScrollView.frame.size.width * self.MoreTabPageControl.currentPage; frame.origin.y = 0; frame.size = self.MoreTabScrollView.frame.size; [self.MoreTabScrollView scrollRectToVisible:frame animated:YES]; self.MoreTabTitle.text = [titles objectAtIndex:self.MoreTabPageControl.currentPage]; // Keep track of when scrolls happen in response to the page control // value changing. If we don't do this, a noticeable "flashing" occurs // as the the scroll delegate will temporarily switch back the page // number. pageControlBeingUsed=YES; } //Create a frame for each page and add the page to the scroll view -(void)setUpPageViews{ //Set up all page views for the more tab for (int i = 0; i < MoreTabPages.count; i++) { //Get the current table view controller page UIWebView *webController= [MoreTabPages objectAtIndex:i]; //Request the URL and load the request NSURL *urll =[NSURL URLWithString:[websites objectAtIndex:i]]; //Run requests in seperate thread dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0); dispatch_async(queue, ^{ NSURLRequest *firstReq = [NSURLRequest requestWithURL:urll]; [webController loadRequest:firstReq]; dispatch_sync(dispatch_get_main_queue(), ^{ //Create a frame for the current table view controller CGRect frame = webController.frame; frame.origin.x = self.MoreTabScrollView.frame.size.width * i; frame.origin.y = 0; frame.size = self.MoreTabScrollView.frame.size; webController.frame = frame; //Add the the current table view controller page to the scroll view [self.MoreTabScrollView addSubview:webController]; //Release the controller object it is no longer needed [webController release]; if(i == 3){ [spinner stopAnimating]; } }); }); } } //Set al the properties for the scroll view and page controll -(void)setScrollandPageViewProperties{ self.MoreTabScrollView.contentSize = CGSizeMake(self.MoreTabScrollView.frame.size.width * MoreTabPages.count, self.MoreTabScrollView.frame.size.height); self.MoreTabScrollView.scrollsToTop = NO; self.MoreTabScrollView.contentOffset = CGPointMake(self.MoreTabScrollView.frame.size.width, 0); self.MoreTabPageControl.numberOfPages = MoreTabPages.count; } -(void)setupSpinner{ spinner.hidesWhenStopped = YES; [spinner startAnimating]; } //Called if the application receives a memory warning - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } //Called when the UIViewController's reference count goes to zero - (void)dealloc { [super dealloc]; [MoreTabPageControl release]; [MoreTabScrollView release]; [MoreTabTitle release]; [MoreTabPages release]; [titles release]; [websites release]; [spinner release]; } @end 尝试为每个网页视图设置最小缩放比例。
[self.aboutWebView.scrollView setMinimumZoomScale:0.1]
如果滚动视图在零缩放时达到零，它将抛出相同的错误。
当使用setZoomScale:animated: method或zoomScale属性将UIScrollView实例缩放到0时，可能会发生仿射变换 ，因此请检查滚动视图。
确保您的zoomScale ， minimumZoomScale和maximumZoomScale设置为至less0.1。
有关：
- 计算UIScrollView的minimumZoomScale
- 更改子视图后，UIScrollView不尊重minimumZoomScale