cách phóng to hoặc thu nhỏ trong uipageviewcontroller?

Question

Tôi có một bộ điều khiển uipageview và đặt một bộ điều khiển xem con trong uipageviewcontroller có tên là contentviewcontroller.

thePageViewController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl navigationOrientation: UIPageViewControllerNavigationOrientationHorizontal options:nil]; 

    thePageViewController.delegate = self; 
    thePageViewController.dataSource = self; 

    thePageViewController.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; 

    contentViewController = [[HBDocumentChildViewController alloc] initWithPDF:PDFDocument]; 
    contentViewController.page = [modelArray objectAtIndex:0]; 
    NSArray *viewControllers = [NSArray arrayWithObject:contentViewController]; 
    [thePageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil]; 

    [self addChildViewController:thePageViewController]; 
    [self.view addSubview:thePageViewController.view]; 
    thePageViewController.view.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height); 
    [thePageViewController didMoveToParentViewController:self]; 
    self.view.gestureRecognizers = thePageViewController.gestureRecognizers; 
    self.view.backgroundColor = [UIColor underPageBackgroundColor]; 

tôi đã thực hiện để tải file pdf vào các trang trong uipageviewcontroller với sự giúp đỡ của một lớp xem cuộn (pdfScrollView) .Công followig là lớp nội dung của uipageviewcontroller và khởi tạo lớp UIScrollView.

#import "HBDocumentChildViewController.h" 

@interface HBDocumentChildViewController()<UIWebViewDelegate> 
{ 
    int currentPage; 
    NSString*localPath; 
} 

@end 

@implementation HBDocumentChildViewController 

#pragma mark - View lifecycle 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 

    // Create our PDFScrollView and add it to the view controller. 
    CGPDFPageRef PDFPage = CGPDFDocumentGetPage(thePDF, [_page intValue]); 
    pdfScrollView = [[PDFScrollView alloc] initWithFrame:self.view.frame]; 
    [pdfScrollView setPDFPage:PDFPage]; 
    [self.view addSubview:pdfScrollView]; 
    self.view.backgroundColor = [UIColor whiteColor]; 
    self.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; 
    pdfScrollView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; 
} 

Sau đây là lớp UIScrollView,

/* 
    File: PDFScrollView.m 
Abstract: UIScrollView subclass that handles the user input to zoom the PDF page. This class handles swapping the TiledPDFViews when the zoom level changes. 
    Version: 2 


*/ 

#import "PDFScrollView.h" 
#import "TiledPDFView.h" 
#import <QuartzCore/QuartzCore.h> 


@interface PDFScrollView() 

// A low resolution image of the PDF page that is displayed until the TiledPDFView renders its content. 
@property (nonatomic, weak) UIImageView *backgroundImageView; 

// The TiledPDFView that is currently front most. 
@property (nonatomic, weak) TiledPDFView *tiledPDFView; 

// The old TiledPDFView that we draw on top of when the zooming stops. 
@property (nonatomic, weak) TiledPDFView *oldTiledPDFView; 

@end 



@implementation PDFScrollView 
{ 
    CGPDFPageRef _PDFPage; 

    // Current PDF zoom scale. 
    CGFloat _PDFScale; 
    CGFloat _PDFScaleH; 
} 


@synthesize backgroundImageView=_backgroundImageView, tiledPDFView=_tiledPDFView, oldTiledPDFView=_oldTiledPDFView; 


- (id)initWithCoder:(NSCoder *)coder 
{ 
    self = [super initWithCoder:coder]; 
    if (self) { 
     self.decelerationRate = UIScrollViewDecelerationRateFast; 
     self.delegate = self; 
    } 
    return self; 
} 


- (void)setPDFPage:(CGPDFPageRef)PDFPage; 
{ 
    CGPDFPageRetain(PDFPage); 
    CGPDFPageRelease(_PDFPage); 
    _PDFPage = PDFPage; 

    // Determine the size of the PDF page. 
    CGRect pageRect = CGPDFPageGetBoxRect(_PDFPage, kCGPDFMediaBox); 
    float actualHeight = pageRect.size.height; 
    float actualWidth = pageRect.size.width; 
    float imgRatio = actualWidth/actualHeight; 
    float maxRatio = 768.0/911.0; 

    if(imgRatio!=maxRatio){ 
     if(imgRatio < maxRatio){ 
      imgRatio = 911.0/actualHeight; 
      actualWidth = imgRatio * actualWidth; 
      actualHeight = 911.0; 
     } 
     else{ 
      imgRatio = 768.0/actualWidth; 
      actualHeight = imgRatio * actualHeight; 
      actualWidth = 768.0; 
     } 
    } 
    pageRect.size = CGSizeMake(actualWidth, actualHeight); 
    UIGraphicsBeginImageContext(pageRect.size); 

    /* 
    Create a low resolution image representation of the PDF page to display before the TiledPDFView renders its content. 
    */ 
    UIGraphicsBeginImageContext(pageRect.size); 

    CGContextRef context = UIGraphicsGetCurrentContext(); 

    // First fill the background with white. 
    CGContextSetRGBFillColor(context, 1.0,1.0,1.0,1.0); 
    CGContextFillRect(context,pageRect); 

    CGContextSaveGState(context); 
    // Flip the context so that the PDF page is rendered right side up. 
    CGContextTranslateCTM(context, 0.0, pageRect.size.height); 
    CGContextScaleCTM(context, 1.0, -1.0); 

    // Scale the context so that the PDF page is rendered at the correct size for the zoom level. 
    CGContextScaleCTM(context, imgRatio,imgRatio); 
    CGContextDrawPDFPage(context, _PDFPage); 
    CGContextRestoreGState(context); 

    UIImage *backgroundImage = UIGraphicsGetImageFromCurrentImageContext(); 

    UIGraphicsEndImageContext(); 


    if (self.backgroundImageView != nil) { 
     [self.backgroundImageView removeFromSuperview]; 
    } 

    UIImageView *backgroundImageView = [[UIImageView alloc] initWithImage:backgroundImage]; 
    backgroundImageView.frame = pageRect; 
    backgroundImageView.contentMode = UIViewContentModeScaleAspectFit; 
    [self addSubview:backgroundImageView]; 
    [self sendSubviewToBack:backgroundImageView]; 
    self.backgroundImageView = backgroundImageView; 

    // Create the TiledPDFView based on the size of the PDF page and scale it to fit the view. 
    TiledPDFView *tiledPDFView = [[TiledPDFView alloc] initWithFrame:pageRect scale:imgRatio]; 
    [tiledPDFView setPage:_PDFPage]; 

    [self addSubview:tiledPDFView]; 
    self.tiledPDFView = tiledPDFView; 
} 


- (void)dealloc 
{ 
    // Clean up. 
    CGPDFPageRelease(_PDFPage); 
} 


#pragma mark - 
#pragma mark Override layoutSubviews to center content 

// Use layoutSubviews to center the PDF page in the view. 
- (void)layoutSubviews 
{ 
    [super layoutSubviews]; 

    // Center the image as it becomes smaller than the size of the screen. 

    CGSize boundsSize = self.bounds.size; 
    CGRect frameToCenter = self.tiledPDFView.frame; 

    // Center horizontally. 

    if (frameToCenter.size.width < boundsSize.width) 
     frameToCenter.origin.x = (boundsSize.width - frameToCenter.size.width)/2; 
    else 
     frameToCenter.origin.x = 0; 

    // Center vertically. 

    if (frameToCenter.size.height < boundsSize.height) 
     frameToCenter.origin.y = (boundsSize.height - frameToCenter.size.height)/2; 
    else 
     frameToCenter.origin.y = 0; 

    self.tiledPDFView.frame = frameToCenter; 
    self.backgroundImageView.frame = frameToCenter; 

    /* 
    To handle the interaction between CATiledLayer and high resolution screens, set the tiling view's contentScaleFactor to 1.0. 
    If this step were omitted, the content scale factor would be 2.0 on high resolution screens, which would cause the CATiledLayer to ask for tiles of the wrong scale. 
    */ 
    self.tiledPDFView.contentScaleFactor = 1.0; 
} 


#pragma mark - 
#pragma mark UIScrollView delegate methods 

/* 
A UIScrollView delegate callback, called when the user starts zooming. 
Return the current TiledPDFView. 
*/ 
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView 
{ 
    return self.tiledPDFView; 
} 

/* 
A UIScrollView delegate callback, called when the user begins zooming. 
When the user begins zooming, remove the old TiledPDFView and set the current TiledPDFView to be the old view so we can create a new TiledPDFView when the zooming ends. 
*/ 
- (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(UIView *)view 
{ 
    // Remove back tiled view. 
    [self.oldTiledPDFView removeFromSuperview]; 

    // Set the current TiledPDFView to be the old view. 
    self.oldTiledPDFView = self.tiledPDFView; 
    [self addSubview:self.oldTiledPDFView]; 
} 


/* 
A UIScrollView delegate callback, called when the user stops zooming. 
When the user stops zooming, create a new TiledPDFView based on the new zoom level and draw it on top of the old TiledPDFView. 
*/ 
- (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale 
{ 
    // Set the new scale factor for the TiledPDFView. 
    _PDFScale *= scale; 
    // Calculate the new frame for the new TiledPDFView. 
    CGRect pageRect = CGPDFPageGetBoxRect(_PDFPage, kCGPDFMediaBox); 
    pageRect.size = CGSizeMake(pageRect.size.width*_PDFScale, pageRect.size.height*_PDFScale); 

    // Create a new TiledPDFView based on new frame and scaling. 
    TiledPDFView *tiledPDFView = [[TiledPDFView alloc] initWithFrame:pageRect scale:_PDFScale]; 
    [tiledPDFView setPage:_PDFPage]; 

    // Add the new TiledPDFView to the PDFScrollView. 
    [self addSubview:tiledPDFView]; 
    self.tiledPDFView = tiledPDFView; 
} 


@end 

Hình dựng trang đang làm việc một cách chính xác, nhưng tôi đã không nhận được phóng to thu nhỏ trong trang/ra hiển thị phương pháp đại biểu view.The UIScrollView không làm việc trong uipageviewcontroller.Xin vui lòng giúp tôi tìm giải pháp cho vấn đề này.

Answer 1

Tôi đã làm cuộn và zoom trong uipageviewcontroller. Tôi đã thay đổi phương thức UIPinchGestureRecognizer ở trên để phóng to và thu nhỏ kích thước trang hiện tại.

-(void)pinchDetected:(UIPinchGestureRecognizer *)pinchRecognizer 

{ 
    if([pinchRecognizer state] == UIGestureRecognizerStateBegan) { 
     // Reset the last scale, necessary if there are multiple objects with different scales 
     lastScale = [pinchRecognizer scale]; 
    } 

    if ([pinchRecognizer state] == UIGestureRecognizerStateBegan ||[pinchRecognizer state] == UIGestureRecognizerStateChanged) 
    { 
     CGFloat currentScale = [[[pinchRecognizer view].layer valueForKeyPath:@"transform.scale"] floatValue]; 
     // Constants to adjust the max/min values of zoom 
     const CGFloat maxScale = 1.5; 
     const CGFloat minScale = 1.0; 

     CGFloat newScale = 1 - (lastScale - [pinchRecognizer scale]); 
     newScale = MIN(newScale, maxScale/currentScale); 
     newScale = MAX(newScale, minScale/currentScale); 
     thePageViewController.view.transform = CGAffineTransformScale(thePageViewController.view.transform, newScale, newScale); 
     lastScale = [pinchRecognizer scale]; // Store the previous scale factor for the next pinch gesture call 
    } 
} 

Sau đó, tôi đã thêm [pdfScrollView setScrollEnabled: YES]; [pdfScrollView setContentSize: CGSizeMake (768, 1100)]; mã trong viewDidLoad của viewController nội dung (HBDocumentChildViewController) để di chuyển các contentView trong lớp uipageviewcontroller.

- (void)viewDidLoad 
    { 
     [super viewDidLoad]; 

     // Create our PDFScrollView and add it to the view controller. 
     CGPDFPageRef PDFPage = CGPDFDocumentGetPage(thePDF, [_page intValue]); 
     pdfScrollView = [[PDFScrollView alloc] initWithFrame:self.view.frame]; 
     pdfScrollView.bouncesZoom = YES; 
     [pdfScrollView setScrollEnabled:YES]; 
     [pdfScrollView setContentSize:CGSizeMake(768, 1100)]; 
     [pdfScrollView setPDFPage:PDFPage]; 
     [self.view addSubview:pdfScrollView]; 
     self.view.backgroundColor = [UIColor whiteColor]; 
     self.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; 
     pdfScrollView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; 
     pdfScrollView.delegate = pdfScrollView; 

    } 

Hãy thử mã này để phóng to và thu nhỏ kích thước trang hiện tại và cuộn nội dung của bộ điều khiển uipageview.

Answer 2

Hãy thử này

UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinchDetected:)]; 
[thePageViewController addGestureRecognizer:pinchRecognizer]; 
pinchRecognizer.delegate=self; 

Phương pháp là

-(void)pinchDetected:(UIPinchGestureRecognizer *)pinchRecognizer 
{ 
    CGFloat scale = pinchRecognizer.scale; 
    thePageViewController.transform = CGAffineTransformScale(thePageViewController.transform, scale, scale); 
    pinchRecognizer.scale = 1.0; 
}