简介
这里介绍两种方法显示PDF，第一种用UIWebView，特色是代码简单，可是无法实现翻页效果。第二中方法利用IOS系统的CGContextDrawPDFPage方法手动实现，代码复杂一些，同时须要配合UIScrollView实现缩放，以及利用UIPageViewController实现翻页的效果。git
方法一：利用UIWebView
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-(void)loadPDF:(NSString*)fileName inWebView:(UIWebView*)webView{ NSString *path = [[NSBundle mainBundle] pathForResource:fileName ofType:nil]; NSURL *url = [NSURL fileURLWithPath:path]; NSURLRequest *request = [NSURLRequest requestWithURL:url]; [webView loadRequest:request]; } |
- 技巧：设置
webView.scalesPageToFit = YES;能够实现pinch放大缩小 - 缺点：没有翻页的动画效果
方法二：利用CGContextDrawPDFPage
CGContextDrawPDFPage
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-(void)drawInContext:(CGContextRef)context atPageNo:(int)page_no{ // PDF page drawing expects a Lower-Left coordinate system, so we flip the coordinate system // before we start drawing. CGContextTranslateCTM(context, 0.0, self.bounds.size.height); CGContextScaleCTM(context, 1.0, -1.0); if (pageNO == 0) { pageNO = 1; } CGPDFPageRef page = CGPDFDocumentGetPage(pdfDocument, pageNO); CGContextSaveGState(context); { CGAffineTransform pdfTransform = CGPDFPageGetDrawingTransform(page, kCGPDFCropBox, self.bounds, 0, true); CGContextConcatCTM(context, pdfTransform); CGContextDrawPDFPage(context, page); } CGContextRestoreGState(context); } |
须要先反转坐标，根据pageNO获取到CGPDFDocumentRef的那一页，直接CGContextDrawPDFPage。github
UIScrollView
配合UIScrollView实现缩放，ZPDFPageController的主要代码：web
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-(void)viewDidLoad{ [super viewDidLoad]; UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds]; scrollView.showsVerticalScrollIndicator=NO; scrollView.showsHorizontalScrollIndicator=NO; scrollView.minimumZoomScale=1.0f; scrollView.maximumZoomScale=3.0f; scrollView.delegate=self; [self.view addSubview:scrollView]; pdfView = [[ZPDFView alloc] initWithFrame:scrollView.bounds atPage:(int)self.pageNO withPDFDoc:self.pdfDocument]; pdfView.backgroundColor=[UIColor whiteColor]; [scrollView addSubview:pdfView]; scrollView.contentSize=pdfView.bounds.size; } - (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{ return pdfView; } |
UIPageViewController
UIPageViewController的TransitionStyle设置为UIPageViewControllerTransitionStylePageCurl（翻页）。其次也是构建UIPageViewControllerDataSource中的两个方法（ZPDFPageModel）。要注意他们返回的是UIViewController，具体实现请参考源码。动画
效果展现
源码下载
PDFDemourl